Where can I get the purchase and sale agreement contract or any other contracts I can use for wholesaling?

If he does not have a mortgage on the property he could list the property for sale or take out a HELOC and pay the back taxes.  

Put aside whether or not this would make sense financially as I still have a lot of numbers to crunch on that end but is it possible to finance this sale for my tenants through an IRA that I have and if so what's the high level process in doing so?

The Zoning Department said they get calls about the property all the time, however it is still for sale +1.5 years.The lots can be redeveloped with single family or multifamily homes. 

Selling through traditional means could mean a 3-4% commission on sales price and that would seem like a lot on a flip property that might already have a average margin.

Since the sale of the property occurred towards the end of the year, in October, the 1031 Exchange was going to receive an Installement Sale treatment and in the event a Like Kind property was not purchased within 180 days the proceeds would have been taxed in 2018.

Sales price $179kClosing and comission $8,800Net profit $13,500.We found the deal off market. 

Not every area bases property tax on actual sales price, but some might.

Your sale price might take a hit but not as much as new roof. 

Even the best sales people will take 6 months to get begin getting paid due to the natural cycle of real estate, and many people don't close a sale for longer than that.