// Creating a CSV file to export Property (As a test)
    @objc private func createCSV() {
        let fileName = "\(Auth.auth().currentUser!.displayName!)-spreadsheet-info.csv"
        let path = NSURL(fileURLWithPath: NSTemporaryDirectory()).appendingPathComponent(fileName)
        var csvText = "Name,Cost,Rent,Building Tax,Property Tax,Yearly Fees,Value Growth,Squared Feet\n"
        var totalTaxAndFees: Double = 0
        var totalRent: Double = 0
        var totalIncome: Double = 0


        for property in properties {
            // Creating line for each Property to add to spreadsheet
            csvText += "\(property.name),$ \(property.buyingPrice),$ \(property.rent),$ \(property.buildingTax),$ \(property.propertyTax),$ \(property.yearlyFees),\(property.valueGrowth),\(property.squaredFeet)\n"


            // Calculating Total tax and Fees yearly
            totalTaxAndFees += ((property.propertyTax + property.buildingTax) * 12) + property.yearlyFees
            // Calculating Total rent Yearly
            totalRent += property.rent * 12

        }
        totalIncome = totalRent - totalTaxAndFees
        csvText += " \nYearly\nTax + Fees,$ \(totalTaxAndFees)\nRent,$ \(totalRent)\nTotal,$ \(totalIncome)\n"
        csvText += " \nMothly\nTax + Fees,$ \(totalTaxAndFees / 12)\nRent,$ \(totalRent / 12)\nTotal,$ \(totalIncome / 12)\n"

        do {
            try csvText.write(to: path!, atomically: true, encoding: String.Encoding.utf8)

            let vc = UIActivityViewController(activityItems: [path], applicationActivities: [])
            vc.excludedActivityTypes = [
                UIActivity.ActivityType.assignToContact,
                UIActivity.ActivityType.saveToCameraRoll,
                UIActivity.ActivityType.postToFlickr,
                UIActivity.ActivityType.postToVimeo,
                UIActivity.ActivityType.postToTencentWeibo,
                UIActivity.ActivityType.postToTwitter,
                UIActivity.ActivityType.postToFacebook,
                UIActivity.ActivityType.openInIBooks
            ]
            present(vc, animated: true, completion: nil)

        } catch {

            print("Failed to create file")
            print("\(error)")
        }
    }
}


First creates a file name using the user's username.

Create the first row of cells to sort Name, Cost, Rent, Building Tax, Property Tax, Yearly Fees, Value Growth, Squared Feet.

Create a for loop for the user's properties' data.

For each property, create a row with the same properties indicated in the first row (Name, Cost, Rent, Building Tax, Property Tax, Yearly Fees, Value Growth, Squared Feet.)

At the bottom of all the properties, fill overall user properties' data.

Lastly, provide the user with options to share the created file.

Add a throw error in case anything fails.