First sorry for the long post....
When I sold my personal residence on land contract some years ago (around 2005 I think it was), it qualified for the section 121 cap gains exclusion. The tenant/owners gave me a down payment and paid me for several years. They then decided they were no longer interested in owning it long term and walked away. So, I took possession back and have been performing a lot of fix-up/updating/refreshing and hope to sell it soon.

Round figures....Originally bought the home for myself for around $100,000. Sold it to them for a land contract sales price of $150,000. They made amortizing payments to me and paid a total of around $15,000 towards the principal.

Again, the gain on sale of $150,000 minus my original $100,000 purchase price would be ignored vis a vis sec 121. My thinking is that when I took the property back, the land contract price of $150,000 would serve as my new cost.

Not sure if it's relevant but I will note that I never put this property back into service so there was never any depreciation on it because it was never rented or ready to rent. It's been vacant for a couple of years and I'm now finishing up the rehab process.

A couple questions. When I do sell it, what tax forms should I use to report it? And, let's say I sell for $165,000 and let's say I've put $10,000 back into it --- how do I incorporate these repair/refresh costs.

Thanks all