public class WTPBuilder
{
    public IList<WTP_block> WTPblocks { get; set; }
    public IList<Contamination> contams { get; set; }
    public IList<FilterMaterial> filtermaterials { get; set; }
    //public List<Price> prices { get; set; }
    public IList<Effort> efforts { get; set; }
    public PriceList priceList { get; set; }
    public double flow { get; set; }
    public double price { get; set; }
    public int longestList { get; set; }
    public string typeofdew { get; set; }
    public string wtp_luxury { get; set; }
    public double pipe_size { get; set; }
    public string pipe_type { get; set; }
    public double overcapacity { get; set; }
    public int duration_days { get; set; }
    public double distance { get; set; }
    public string discharge_point { get; set; }
    public bool prov1 { get; set; } // these will go in a list at some point.
    public bool prov2 { get; set; }
    public bool prov3 { get; set; }
    public bool prov4 { get; set; }
    public bool prov5 { get; set; }
    public bool prov6 { get; set; }
    public bool prov7 { get; set; }
    public bool prov8 { get; set; }
    public bool prov9 { get; set; }
    public bool prov10 { get; set; }
    public bool prov11 { get; set; }
    public bool prov12 { get; set; }
    public WTPBuilder()
    {
        //WTPblocks = new IList<WTP_block>();
        //filtermaterials = new List<FilterMaterial>();
        //contams = new List<Contamination>();
    }

    public WTPBuilder(List<Contamination> conta, double flow, string typeofdew, int duration_days, string dischargeto, string wtp_luxurity)
    {
        this.flow = flow;
        this.contams = conta;
        this.typeofdew = typeofdew;
        this.duration_days = duration_days;
        this.discharge_point = dischargeto;
        this.wtp_luxurity = wtp_luxurity;
    }
}

namespace App2.Models
{
public class WTP_block
{
    [Key]
    public int id { get; set; }
    [Required]

    public string name { get; set; }
    [Required]
    public double size { get; set; }
    public double? length { get; set; }
    public double? width { get; set; }
    public double? height { get; set; }
    public double? weight { get; set; }
    public bool necessity { get; set; }

    public string uniquename()
    {
        string[] s = { this.name, this.size.ToString() };
        return string.Join("_",s);
    }
}
}

[HttpPost]
    public IActionResult remove_wtp_part(int? id, WTPBuilder model)
    {
        if (ModelState.IsValid)
        {
            var wtpblock = model.WTPblocks.SingleOrDefault(b => b.id == id); //here model.WTPblocks.Count = 0 or null if this list is not initialized in the constructor WTPBuilder()
            model.WTPblocks.Remove(wtpblock);
            return RedirectToAction("CreateOldWTP", "WTPBuilder", new { wtp = model });
        }

        return View("Index"); //random never reaches it as model.state is true...
    }

@model App2.Models.WTP_block
@Html.HiddenFor(x => x.id)
@Html.EditorFor(x => x.name)
@Html.EditorFor(x => x.size)
@Html.EditorFor(x => x.length)
@Html.EditorFor(x => x.width)
@Html.EditorFor(x => x.height)
@Html.EditorFor(x => x.weight)
@Html.CheckBoxFor(x => x.necessity)

@model App2.Models.WTPBuilder
@{
    ViewData["Title"] = "InputUse";
}

<h2>WTP WAS BUILT</h2>

<h1>The WTP contains</h1>
<h3>Flow: @Model.flow</h3>
<h3>Type: @Model.typeofdew </h3>
<h3>Blocks: @Model.longestList</h3>
<h3>WTP Luxury status: @Model.wtp_luxury</h3>
<h3>WTP pipe type: @Model.pipe_type</h3>
<h3>WTP pipe size: @Model.pipe_size</h3>

<h3>WTP parts</h3>
<table class="table">
    <thead>
        <tr>
            <th>
                @Html.DisplayNameFor(model => model.contams)
            </th>
            <th>
                @Html.DisplayNameFor(model => model.filtermaterials)
            </th>
            <th>
                @Html.DisplayNameFor(model => model.WTPblocks)
            </th>
            <th>
                @Html.DisplayNameFor(model => model.WTPblocks[0].size)
            </th>
        </tr>
    </thead>

    <tbody>

        @for (int i = 0; i < Model.longestList; i++)
        {
            <tr>
                @if (i < Model.contams.Count)
                {
                    <td>@Html.DisplayFor(modelItem => Model.contams[i].Name)</td>
                }
                else
                {
                    <td></td>

                }
                @if (i < Model.filtermaterials.Count)
                {
                    <td>@Html.DisplayFor(modelItem => Model.filtermaterials[i].Name)</td>
                }
                else
                {
                    <td></td>

                }
                @if (i < Model.WTPblocks.Count)
                {
                    <td>@Html.DisplayFor(modelItem => Model.WTPblocks[i].name)</td>
                    <td>@Html.DisplayFor(modelItem => Model.WTPblocks[i].size)</td>
                    <td><a asp-action="getEfforts" asp-route-id="@Model.WTPblocks[i].id">show Efforts</a>|</td>
                    <td>
                        @using (Html.BeginForm("remove_wtp_part", "WTPBuilder", new { id = Model.WTPblocks[i].id }))
                        {
                            @Html.HiddenFor(m=>m.WTPblocks[i].id)
                            <input type="submit" value="Remove"/>
                        }
                    </td>
                }
                else
                {
                    < td ></ td >
                }
            </tr>
        }
    </tbody>
</table>
HERE ENDS THE INTERESTING PART, I ASSUME!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
<h3>Efforts to install</h3>
<table class="table">
    <thead>
        <tr>
            <th>
                @Html.DisplayNameFor(modelItem => Model.efforts[0].WTP_block_name)
            </th>
            <th>
                @Html.DisplayNameFor(modelItem => Model.efforts[0].Name)
            </th>
            <th>
                @Html.DisplayNameFor(modelItem => Model.efforts[0].category)
            </th>
            <th>
                @Html.DisplayNameFor(modelItem => Model.efforts[0].effort)
            </th>
            <th>
                @Html.DisplayNameFor(modelItem => Model.efforts[0].unit)
            </th>
            <th>
                @Html.DisplayNameFor(modelItem => Model.efforts[0].temp_section)
            </th>
            <th>
                @Html.DisplayNameFor(modelItem => Model.efforts[0].wtp_luxurity)
            </th>
        </tr>
    </thead>

    <tbody>
        @for (int i = 0; i < Model.efforts.Count; i++)
        {
            <tr>
                <td>@Html.DisplayFor(modelItem => Model.efforts[i].WTP_block_name)</td>
                <td>@Html.DisplayFor(modelItem => Model.efforts[i].Name)</td>
                <td>@Html.DisplayFor(modelItem => Model.efforts[i].category)</td>
                <td>@Html.DisplayFor(modelItem => Model.efforts[i].effort)</td>
                <td>@Html.DisplayFor(modelItem => Model.efforts[i].unit)</td>
                <td>@Html.DisplayFor(modelItem => Model.efforts[i].temp_section)</td>
                <td>@Html.DisplayFor(modelItem => Model.efforts[i].wtp_luxurity)</td>
                <td><a asp-action="EditEffort" asp-route-id="@Model.efforts[i].id">Edit</a></td>
            </tr>
        }
    </tbody>
</table>

Mobilisation ( total = @Html.DisplayFor(Model => Model.priceList.total_price_mob) )
<table class="table">
    <thead>
        <tr>
            <th>
                Name
            </th>
            <th>
                Amount
            </th>
            <th>
                Price
            </th>

        </tr>
    </thead>

    <tbody>
        @foreach (var item in Model.priceList.prices_mob)
        {
            <tr>
                <td>@Html.DisplayFor(modelItem => item.Key)</td>
                <td>@Html.DisplayFor(modelItem => Model.priceList.quantities_mob[item.Key])</td>
                <td>@Html.DisplayFor(modelItem => item.Value)</td>

            </tr>
        }
    </tbody>
</table>

De-Mobilisation ( total = @Html.DisplayFor(Model => Model.priceList.total_price_demob) )
<table class="table">
    <thead>
        <tr>
            <th>
                Name
            </th>
            <th>
                Amount
            </th>
            <th>
                Price
            </th>

        </tr>
    </thead>

    <tbody>
        @foreach (var item in Model.priceList.prices_demob)
        {
            <tr>
                <td>@Html.DisplayFor(modelItem => item.Key)</td>
                <td>@Html.DisplayFor(modelItem => Model.priceList.quantities_demob[item.Key])</td>
                <td>@Html.DisplayFor(modelItem => item.Value)</td>

            </tr>
        }
    </tbody>
</table>

Operation and Maintenance ( total = @Html.DisplayFor(Model => Model.priceList.total_price_operation) )
<table class="table">
    <thead>
        <tr>
            <th>
                Name
            </th>
            <th>
                Amount
            </th>
            <th>
                Price
            </th>

        </tr>
    </thead>

    <tbody>
        @foreach (var item in Model.priceList.prices_operation)
        {
            <tr>
                <td>@Html.DisplayFor(modelItem => item.Key)</td>
                <td>@Html.DisplayFor(modelItem => Model.priceList.quantities_operation[item.Key])</td>
                <td>@Html.DisplayFor(modelItem => item.Value)</td>

            </tr>
        }
    </tbody>
</table>

Rent ( total = @Html.DisplayFor(Model => Model.priceList.total_price_rent) )
<table class="table">
    <thead>
        <tr>
            <th>
                Name
            </th>
            <th>
                Amount
            </th>
            <th>
                Price
            </th>

        </tr>
    </thead>

    <tbody>
        @foreach (var item in Model.priceList.prices_rent)
        {
            <tr>
                <td>@Html.DisplayFor(modelItem => item.Key)</td>
                <td>@Html.DisplayFor(modelItem => Model.priceList.quantities_rent[item.Key])</td>
                <td>@Html.DisplayFor(modelItem => item.Value)</td>
            </tr>
        }
    </tbody>
</table>

<h3>Complete Price List</h3>
<table class="table">
    <thead>
        <tr>
            <th>
                @Html.LabelFor(m=>m.priceList.prices_all[0].id)
            </th>
            <th>
                @Html.LabelFor(m => m.priceList.prices_all[0].id)
            </th>
            <th>
                @Html.LabelFor(m => m.priceList.prices_all[0].EkdT)
            </th>
            <th>
                @Html.LabelFor(m => m.priceList.prices_all[0].size)
            </th>
            <th>
                @Html.LabelFor(m => m.priceList.prices_all[0].unit)
            </th>
            <th>
                @Html.LabelFor(m => m.priceList.prices_all[0].price)
            </th>
            <th>
                @Html.LabelFor(m => m.priceList.prices_all[0].unit_p)
            </th>
            <th>
                @Html.LabelFor(m => m.priceList.prices_all[0].rent)
            </th>
            <th>
                @Html.LabelFor(m => m.priceList.prices_all[0].unit_r)
            </th>
        </tr>
    </thead>

    <tbody>
        @for (int i = 0; i < Model.priceList.prices_all.Count; i++)
        {
            <tr>
                <td>@Html.DisplayFor(modelItem => Model.priceList.prices_all[i].id)</td>
                <td>@Html.DisplayFor(modelItem => Model.priceList.prices_all[i].name)</td>
                <td>@Html.DisplayFor(modelItem => Model.priceList.prices_all[i].EkdT)</td>
                <td>@Html.DisplayFor(modelItem => Model.priceList.prices_all[i].size)</td>
                <td>@Html.DisplayFor(modelItem => Model.priceList.prices_all[i].unit)</td>
                <td>@Html.DisplayFor(modelItem => Model.priceList.prices_all[i].price)</td>
                <td>@Html.DisplayFor(modelItem => Model.priceList.prices_all[i].unit_p)</td>
                <td>@Html.DisplayFor(modelItem => Model.priceList.prices_all[i].rent)</td>
                <td>@Html.DisplayFor(modelItem => Model.priceList.prices_all[i].unit_r)</td>
                <td><a asp-action="editThePrice" asp-route-id="@Model.priceList.prices_all[i].id">Edit Price</a></td>


            </tr>
        }
    </tbody>
</table>

<div class="row">
    <div class="col-sm-8">
        <div class="form-inline">
            <div class="form-group">
                @Html.DisplayFor(m => m.prov1)
            </div>
        </div>
        <div class="form-inline">
            <div class="form-group">
                @Html.DisplayFor(m => m.prov2)
            </div>
        </div>
        <div class="form-inline">
            <div class="form-group">
                @Html.DisplayFor(m => m.prov3)
            </div>
        </div>
        <div class="form-inline">
            <div class="form-group">
                @Html.DisplayFor(m => m.prov4)
            </div>
        </div>
        <div class="form-inline">
            <div class="form-group">
                @Html.DisplayFor(m => m.prov5)
            </div>
            <div class="form-inline">
                <div class="form-group">
                    @Html.DisplayFor(m => m.prov6)
                </div>
            </div>
            <div class="form-inline">
                <div class="form-group">
                    @Html.DisplayFor(m => m.prov7)
                </div>
            </div>
            <div class="form-inline">
                <div class="form-group">
                    @Html.DisplayFor(m => m.prov8)
                </div>
            </div>
            <div class="form-inline">
                <div class="form-group">
                    @Html.DisplayFor(m => m.prov9)
                </div>
            </div>
            <div class="form-inline">
                <div class="form-group">
                    @Html.DisplayFor(m => m.prov10)
                </div>
            </div>
            <div class="form-inline">
                <div class="form-group">
                    @Html.DisplayFor(m => m.prov11)
                </div>
            </div>
            <div class="form-inline">
                <div class="form-group">
                    @Html.DisplayFor(m => m.prov12)
                </div>
            </div>
        </div>
    </div>
</div>

@using (Html.BeginForm("remove_wtp_part", "WTPBuilder", new { id =     Model.WTPblocks[i].id }))
                    {
                        @Html.HiddenFor(m=>m.WTPblocks[i].id)
                        <input type="submit" value="Remove"/>
                    }