This is of concern for me because I have seen enormous problems caused by a careless repairman.

I'm just concerned about putting in an enormous amount of time to trying to build a business around this niche, and realize that investors don't need me to help them sell or buy.

This is a really nice service to generate an enormous amount of mailers to the property owners in literally minutes.  

I'll have to disagree: a human can a.) only deal with a small number of data points and b.) only fathom very simple relationships between them (at least when it comes to the numbers).An algorithm, on the other hand can learn complicated mathematical relationships (also nonlinear ones that are especially hard for humans to deal with) between all the variables and the price, can do so unbiased (theoretically), and take into account an enormous number of data points.

I know in 1991 you would have had an enormous audience.

This post would be enormous if I addressed each of your individual points, so please know that I read them all and I'm incorporating their spirit into my own ethic.Thanks again for caring enough to post. 

Flipkey brings me about 10% of my rentals and I'm considering moving to booking.com (though they're so enormous it's difficult to communicate with them and get signed up).  

First politically, which then puts an enormous financial strain on the developer.   

People will continue to see the enormous value of living in the city.

However, this way the seller gets a far more certain result, and gets it much more quickly.â€Lender – Enormous Benefits“The lender benefits enormously as well.