Some other items came up that needed repaired and I've used the property for other purposes since then.

When he became incapacitated and could no longer visit his unit, approximately 7 years ago, another family member, who had assisted him in maintaining the building, began utilizing the space for storage, vehicle repairs etc.

Do you landlords allow tenant to make repairs/updates to the property themselves on their dime?

Buyer wanted some plumbing repairs done at the property and he send me an amendment for repairs.

I'd live in the other unit and still pay close to $600u/mon for utilities, taxes, insurance, repairs and capex.

First one is a basic intro (we buy houses, want to buy 2 in your town this spring, selling direct is great for X reasons, let me know if you want an offer), second one highlights what type of sellers typically like to sell to investors (own timeline, no hassle, house needs repairs etc), third mailing is a simple postcard that has similar message on it, fourth mailing is a letter saying I've reached out before and thought you might find these FAQs useful (and I include a 4 pg FAQ distilled from my website)-- I expected that letter to have more response (you'll see above the 4th mailing had a <1% response rate) and it may be that ppl are waiting til after Easter to call, as I get more calls after holidays when ppl have had time to talk to their family.How to track all of this... you can guess by now that I'm super data oriented.

I try to line up several showings in one day while I'm staying busy cleaning or repairing.

I lend them money and create a note that is secured to the real estate.The money is for repairs on the RE property itself. 

I have a tenant that's moved out and I've been doing much of the repair work myself.  

As to the original question the seller is bound to the original contract but of course not obligated to do any repairs/price reductions unless agreed upon.