It's been about four years since I quit building in one of the lowest cost areas of the Mid-Atlantic states. At that point, costs for very basic new construction was in the $100 a foot range. You might want to think about installing a modular up on piers, if you have a very tight budget. I only mention this because we spend our winters north of Tampa, and the "nature coast" area, of Homosassa, Crystal River, etc has a lot of existing, and new construction, being done this way on, and near, the coast. Obviously, this is not a concrete block house, but I would encourage you to double check the info. on this. A lot of codes in FL. require concrete block for structures on grade, or piers, then stick framing for the higher floors. Now this is all based on what I have observed, and certainly doesn't mean that you aren't 100% correct, and that the specific lot you are speaking of requires a higher level of hurricane resistance. The concept of elevating homes in coastal zones is interesting. A lot of the effort is because most residential construction, block, or wood frame, does really poorly when it deals with tidal surge and waves, even seemingly minor waves. A house that would be totally destroyed if it sat at grade level, and heavily damaged, or washed away, if it was up on a tall block basement, can ride out near armageddon storm, if it's tightly strapped to 12-14 ft. tall piers. A lot of people don't realize that many fancy three story beach houses have an entire first floor built around a pier structure, and the walls, and interior of the first floor are designed to be swept away, in a severe storm.