>we have a 44foot csy right now and looking at trawler when retire to do the icw.<.
Anything from a jet ski to a condom dink will run the AICW or the Loop.
What makes you comfortable in terms of interior volume will be easy coming from a sail boat.
The big question is AFTER the loop, will you be keeping the boat for future uses or dumping it .
If its a one shot deal a very modest boat ,about 28-30 ft like a Bayliner will do just fine , and should cost under $5K and some work.
The boat will be gas powered , but will probably only cost an extra GPH , so in a 6000mile cruise you might burn 3 GPH vs a diesel at 2 GPH at 6 mph.
This extra 1000Gal of fuel may add $4000 to the trip expense , but the tiny price to get the boat , and the ease/speed with which you can sell it should still even out.
IF repair is needed the advantage will be all to the gas boat , a $6000 replacement engine vs a $30,000 replacement could be a trip stopper.