C# Code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using GTA;
using GTA.Native;

namespace TrackersV
{
    public class TrackersV : Script
    {
        public TrackersV()
        {
            KeyDown += (sender, e) =>
            {
                if (e.KeyCode == Keys.J)
                {
                    Entity Target;
                    Target = Game.Player.GetTargetedEntity();
                    if (Target != null)
                    {
                        if (Target.CurrentBlip == null)
                        {
                            BlipColor blipColor;
                            if (Game.Player.Character.Model == PedHash.Michael)
                            {
                                blipColor = BlipColor.Michael;
                            }
                            else if (Game.Player.Character.Model == PedHash.Franklin)
                            {
                                blipColor = BlipColor.Franklin;
                            }
                            else if (Game.Player.Character.Model == PedHash.Trevor)
                            {
                                blipColor = BlipColor.Trevor;
                            }
                            else
                            {
                                blipColor = BlipColor.Freemode;
                            }
                            Target.AddBlip();
                            Target.CurrentBlip.Sprite = BlipSprite.BigCircle;
                            Target.CurrentBlip.Color = blipColor;
                            Target.CurrentBlip.Name = Target.Model.ToString();
                        }
                    }
                    else if (Target.CurrentBlip != null)
                    {
                        Target.CurrentBlip.Remove();
                    }
                }
            };
        }

    }
}