Also would need more background/history on Mike the Builder.

Maybe you are talking about building more townhome style, which, I have a builder friend that just built a four townhomes and are selling fine, as well.  

New build maybe a bit aggressive getting into real estate unless you have a builder as a partner in a deal to see the full steps or stages that go into new builds.Why new build?

I have a builder friend who tore down two houses and put up 3 townhomes on those two lots.  

Have some buffer in your estimate (you will always go above your budget 90% of the time).Your builder is the real MVP here.

Seems like the few people I talked to that are selling land in Florida are trying to sell it above retail without understanding that most of their potential buyers are going to be builders. do Not buy land in FLA without doing full due diligence  on all aspects . there are environmental gotchas that you need to fully suss out prior to waiving due diligence

But in terms of a new home builder wanting to buy 109 acres in that location - I just don't see that being very likely (IMHO). 

Meeting with Builder Banc later today and demanding my money back.

@Connor Williams yeah, what the above posts stated but it's formally called "Forward Commitment" when a builder does it (if you want to google more on it).  

What I did find is that as a builder in eastern tennessee, I could build STR cabins for less than 70% LTV so that I could effectively BRRR my way into growth without coming out of pocket for a down payment.Now it does take a lot more cash to do because as a builder I have to front a lot of money at times (land, permits, each stage of construction while I'm waiting on the draw).