You cannot depreciate the portion of the purchase attributed to the value of the land. 

I attribute the failure rate to 2 things that MOST Realtors don't do - 1. prospect/cold call for new business 2.

Typically most states where you are NOT a resident only effectively tax income specifically attributable to that state in their allocation and appointment calculations. 

If his numbers are less than you paid, then you can ask, but I don't think you should have any expectation of getting refunds.You are allowed reasonable actual damages from the delay, but if you didn't get revised timeframe from added work it'd be real easy for him to layout five months worth of labor on top of the original timeframe and attribute it to changes you requested.This sounds less like, "I overpaid" and more, "I didn't manage".

That's clearly not what you're trying to do, but you do need to be sure to stand out from those guys.

I have a realtor now but it's really rough around here and all-cash offers seem to stand out the most.

As a realtor and investor in the STR space in Destin, I can attest that there are plenty of terrible options and few agents that stand out. 

I'd add something to it so you can stand out. 

Then you learn the ropes first-hand and can later say your attribution as part of the overall venture was whatever it was. 

There are so many options available for student housing, you really have to have competitive rent and stand out from the other options.