Just keep in mind you need the original HUD-1, and not the one from the refi. Now if you still have the tax return from any of the years you rented it (preferably the one from the tax year you converted it to personal use) the 4562 in that return titled "Depreciation and Amortization Report" will have your original costs basis, which is what you need for reporting the sale correctly. Just add together the amounts in the Cost (Net of Land) and Land columns from that 4562, and that will give you your cost basis. Note that the total you get there has already taken into account any deductible sales expenses and the such, that were incurred and claimed on that original purchase.
