In that case have your realtor submit an amendment for an extension period. 

All new builds in this area are $300k+ and there extensive plans to build highways to this town.

I would hope the work wouldn't be that extensive, but you never know.

(or maybe have some great sources for finding undervalued deals) My girlfriend and I have spoken extensively about doing this, and we are both on the same page.For this example I will use a property that is currently available and listed for $815,000.We would be doing an FHA loan.

How do you get to know a market like this without extensive research that can take months by literally finding out what all the neighborhoods are, exploring all of them, talking to people in all the neighborhoods, etc.?

Ex) Don't give rent due date extensions for a tenant who waves to you everyday vs never giving one to a tenant to repeatedly flips you off. 

I have extensive experience with PM in Cleveland .

Tampa has appreciated extensively recently and buying a home for $95000 is really difficult.The only possible alternative is buying a distressed home and BRRRing it.

After kicking the can down the road for about 6 months the "Bank" came back and said they had a better offer of $20k over my offer and were planning to let my offer expire after 4 extensions unless I increased my offer, which my realtor convinced me was still a good deal.

At this point, you should request that the seller signs an extension of time for closing.