I could add the "rent credit" on top of the market rent, but then that's a $400-$600/month premium on top of the rent that's supposed to go towards the purchase price.

A few additional savings hacks I layered w insurance, was to move deductible up and find break even sweet spot on annual premium.

If you are just picking up "deals" hoping someone will pay a premium in a struggling market, then it will be tough for anyone to sell. no matter how many lists, emails, or phone calls you make. 

It's like the Zillow Estimates... it just aggregates the data from across the board, which is a good start, but it won't account for nuance and detail (e.g. a corner property selling for a 5% premium compared to non-corner).

U can now advertise it as such and charge a premium i would think 

Well gents, let the OP decide when he gets an opportunity to try the system, otherwise, its the so called spammers words against the premium stables of BP.

Then there is a state like Colorado, where the bidding process is done by paying a premium.

Screen my tenants very strictly and rent in premium locations so that works best for me.

Sure, but I agree that until you really know your problems with scale you can't justify the cost of a custom or premium software solution.

I believe there is opportunity out there for offering premium inventory.