I was thinking of slowly raising rents until we get close to market.

Does anyone have any experience with raising private money for STRs?  

@Corby Goadei obviously agree with everything you said... but I assume these folks are just trying to look out for OP.and it seems like there are a lot of people that come on BP because they read Rich Dad Poor Dad, or watched a Brandon Turner webinar, and then spend a bunch of money on a random property, get crushed by capex, and disappear.i think the points / 'objections' raised are valid. 

I plan to be raising the rents on them because they are currently paying about 40% under fair market rent.

My gut is he is going to raise his prices for the next one to take a bit more of the pie.

Ugh, they raised mine when I was renewing in February by like 50%!

I was raised in fear of debt, my parents went bankrupt with their flower business when I was little.

Capital can always be borrowed/raised as well, you just have to have a good enough of an opportunity to support the debt and compensate you for the risk. 

After 20 years of buying and selling real estate this morning it occurred to me that if somebody offers to sell their house for let’s say $250,000 “as is” and you agree to pay that exact price with no contingencies, but other people are interested in the property , then that seller can just raise his price and not sell the property for the price “advertised”.

You do have Loopnet, Crexi, and other auction sites, but those deals have already been looked at.It depends upon your knowledge, and the ability to either deploy your own capital or raise it where you should start.