If you get down to SD you could possibly get a mooring
. Its not dry storage
and all but it is in your budget
. Temp moorings cost $225 a month and if you were able to get assigned a "full time" mooring
it would be around $140 a month most likely.
Assuming you get a "full time" mooring ($140/ month) you may be able to get someone or some company to look after your boat while on the mooring for the rest of the $10/foot budget
. I honestly have no idea what this kind of "boat baby sitting" costs or what you get for the costs but it may be worth looking into if you're running out of options.