Investors not giving realistic values.

That may be a bit more realistic.  

I believe that $750,000 for the house is realistic (of course $750,000 -6% realtor fee leaves a net of $705,000) – I am debating getting a real estate license to help cut costs.

Secondly make sure you qualify your buyer - you need to know his buying criteria and if he is realistic (pricing).

I might make some mistakes on the first few, but hopefully those mistakes will be minimal.My goal, whether realistic or not, is to own 15-20 rental properties within 4-6 years.

Way Too many variables but $70-90 is more realistic for a gut rehab with 2nd floor addition.  

Only realistic way IMO to earn money transacting real estate with little funds.

I think realistically, your cap expectations are a bit too high for Florida.

There is a possibility that if I hold onto the place for another 5-10 years that I could make $400-800k in profit...sounds crazy but totally realistic if uptown values ever get closer to downtown ones.

Realistically, I would probably only be contemplating nailing down a tarp if either a big tree branch or trunk fell on it (in which case I'm probably in for a new roof anyway, or at least major repairs), or we had a tornado or really strong winds (again, new roof is likely).The only roof problem I've ever had on my personal residence is when I first bought this house; part of it had been re-roofed on a DIY basis.