Very often I have tenant buyers automatically thinking that the lease payment they make every month while the are living in the Rent to Own property while they are working on obtaining a mortgage loan goes toward reducing the selling price of the Rent to Own property. 

Maybe more.So between down payment, closing costs and repairs, I'd have to front somewhere around $50K - $60K, which I don't have.The strategy that I am considering is finding a hard money lender for this initial costs, with the idea that I pay back all at once when I refinance.On paper, it seems a good prospect for which may be worth to due a solid due diligence but I want to make sure my strategy is entirely doable and be aware of the risks I have to keep in mind. 

Since I am thinking about investing in this sector I would like to find a resource that can show me all of the vacant box stores waiting for a new buyer?

Agreed, find a buyer’s agent to suvomit your offer.  

I gave the buyer more money (through offer and interest income), but I saved almost $10k cost to me, with higher CF, in the process.

After all contingencies have been met, buyer will get primary position, assuming no other buyer's have met this criteria before them."

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Does it fall to the seller or buyer?

All information in listing should be verified by buyer prior to purchase..

Also, the association controls finances, insurance and many other things, a friend of mine has a condo in a unit mainly controlled by Canadians that are seasonal, in their infinite wisdom they decided to not maintain flood insurance for the development (they are in a flood zone)  now the units are unfinanceable , so the values are lower because only cash buyers can buy in the building.