I had an insurance quote of $538/yr for the whole building, but most of their build sites are in unspecified flood zones so you'll need an elevation certificate for accurate flood premium which could be another $800-1400/yr. 

If you zoned for 3+ units, then make sure that the first floor elevation is high enough to meet BFE, otherwise you will not be able to get a permit (and may not be able to ensure the space on a flood policy).

It would be costly (commercial elevator alone would be pricey. 

Acres and acres of weeds and dead grass.We were teens into sports and used to the high elevations but we literally mowed till we dropped.So many nice older homes and in some cases almost entire new subdivision and streets just vacant....

Have your 30 second "elevator speech" very well rehearsed, because if you interrupt my bourbon sippin' time by knocking on my door on a weekend, I better interested in the first 10 of those seconds .. or else that door is getting shut in a hurry.Sit down and write out every single question you think a homeowner might ask you, and have an answer.

The property has an elevated wood dining room and kitchen floor that stands above the rest of the living area, which all sits on a slab foundation.

I want to buy some foreclosed land that has over 100 feet of elevation gain on the property.  

Now I know in the future to get an elevation certificate as a contingency with my offer.

Pilings or stilts usually means you're in a flood zone and the property needs to be elevated to be above the minimum flood elevation.  

However, the children have to be tested for elevated lead levels.