building on a loy with coastal lake frontage

Pretty much every lot I've seen on a coastal lake is in a higher risk flood zone. I think that just goes with the territory. Not sure about the lakes more northward though.

Not sure about added restrictions, but I think any time you build something on the lake, like a dock, or whatever, you need a dep permit. Someone who's actually done something like that could confirm.

Yes, there are different requirements for setbacks, landscape buffers, etc. You should contact the planning department or research the County's land development code for specifics. An easier route would be to enlist the assistance of a licensed, local realtor and have them walk you through the details. They can also track down the flood insurance requirements for you.

I've built 3 houses on Grayton/Western Lake. None of them are in a flood zone that requires more than the standard
FEMA insurance. If you have more specific questions, feel free to PM me and I'll answer the best I can. But the county building department is probably more accurate with answers than I am.

The county Building Dept would have all your answers. Each piece of property is shown on their county Flood Zone Map and that would determine the type of insurance you would need, and also the requirements to build according to the Florida Building Code for that particular zoning. I woud be glad to help you with this, as I am a licensed Florida Contractor and it can sometimes be daunting to get through all the paperwork for a building permit.