We do this all the time. Rent at a local agency on the beach where we live and drop it off at the airport the next day. We live in the Tampa area and usually drive over to Fort Lauderdale the day before and stay overnight. We have dinner at our favorite steakhouse and call it a night. Next morning drive to airport and drop it off. It's worked for us for years--through JetBlue and now Spirit (wish JB still doing it, but it is what it is). Most of the time now we just fly from SXM to TPA, pick up our car and drop off at our local beach agancy.