If I understand correctly you'd be purchasing the land, and improving it and splitting it into the appropriate "buildable lots". 

Many investors make the mistake of over-improving their purchases in Class C/D areas, which when damaged by Class C/D S8 tenants - costs them thousands.Another fallacy of S8 investing is that the S8 Caseworker will keep the S8 tenant inline by threatening to take their voucher away.- The reality is this depends on each individual caseworker.

Ultimately I had a vision for how this particular home could easily be improved and rented for top market without much headache.How did you find this deal and how did you negotiate it?

People think it's so easy to just find a deal that when improved, is going to give you a 25% equity position so you can get all your money back when you refi.

The price was low in 2014, today that same price is riduculously low, and the buyers in 2014 improved the property tremendously and recently re-sold for $230,000, good for them! 

These are typically located in lesser-known vacation rental markets, but have very strong fundamentals and great room for improvement. 

@Richard NguyenHere are some of the downsides of putting real estate into a self directed IRA or 401k.No tax deductions: You can’t claim deductions for property taxes, mortgage interest, depreciation, repairs, improvements and other property-related expenses.Property expenses: All expenses, repairs, and maintenance costs must be paid with IRA or 401k funds, and you must pay others to do repairs and manage the property.

You'll also want to consider if each lender provides funding for renovations/improvements.

You will benefit from better rates and lower cost lumber now, so that will help make up for some of the added carry and perhaps the market conditions have even improved? 

I bought a multifamily property that was undervalued, so working on renovations and improvements now.