Tanner, Im a contractor in the Tampa Bay Area and will do my best to answer your questions. I will slightly over price items with the mindset of expect the worst and hope for the best.
I will start with by saying your 30k budget is ambitious and completely dependent on the land you buy due to...
Do it, block has a horrible r value. With foam injected in it it can achieve an r value of 11.
Also highly recommend radiant barrier with a ridge vent and vented soffits.
You should have several bond beams for horizontal reinforcement, and possibly some tie backs. The real answer requires real load calcs and not just guestamates.
And why not use dirt fill compacting it every foot and get compaction test for every lift.
Is 57 rock a northern frost line thing I...
Not only are you suppose to have rebar tied to the footer every four feet but also have a U block with rebar in it every 48" to form a lintel. Sounds like poor design. Luckily no walls above that are up!
At four times the price! 2k is pretty attainable for a home garage, I think this could end up having some neat home applications. Custom car parts and designs.
On another note... Just imagine, this could take keying someones car to whole new level! CNC etched dong on someones hood for taking up...
Use Simpson h10 straps... No way to install it incorrectly, double your uplift loads per truss. No special nails other than be sure to use 8d x 1 1/2", a palm nailer ideal for install.
since your width (only 16') is at a premium I would put the 36" Work table and 36" welding table at the very front, leaving you still with 21' depth. I would try to leave the wall with the windows with nothing of significant depth. Meaning hanging maybe air hoses and shelving up high. Maybe...
Yeah, the price is in store.... I think at that price it would make an awesome light duty tool chest... Definitely going to pick one up now thanks to th GJ influence