We bought a beach...and a wetland

[Firm]

Looks cozy, would be nice right near the beach. Would give you a spot to stay while you work on the bigger building too.  Could you get a trailer in there? I've seen some pretty nice new trailers, if I had a property like that I'd seriously consider one as a quick way to get something setup.

[RRocket]

So, design us a cottage.

We have a bit of a change of sequence of the development.  We now want a small cottage first, as near the beach as possible, which is about 300 feet past where we want the 'bigger'cottage and garage.

We think 16'x28', maybe 30', with a loft over half of it, is a good size.  I've seen a lot of floorplans, none of which work overall, but we can take parts of them and piece something together. 
This is about closest so far; https://www.etsy.com/ca/listing/1537728379/16x28-modern-cabin-house-plans-tiny
...but with a bit more roof pitch and less windows, etc.   

Almost sounds like you want a large version of a Bunkie.