I agree with the posters above. Cutting requires a lot of room which may not be exclusively yours during the retreat. Short jobs and trimming are fine but cutting out a whole quilt can be problematic. I like to take projects that are cut out and organized or come in small increments like a set of blocks of the month. Do one at a time.
Some retreats are cramped for sewing space too so for those retreats I dont want to be trying to manipulate a whole quilt while sewing large borders. Again blocks or small projects are great.
If you have any kind of back issue, consider taking your own rolling sewing chair. Mine is big but fits in the back seat and I roll it into the retreat. Only one retreat I go to has comfortable chairs with back support.
Dont forget your clothes like I did for the last retreat. Got 3 hours away from home and had to backtrack to meet up with husband and get clothes and medicine. Dont lock your keys in the trunk like I did a couple of years ago. Easy to do. I was lucky and had most everything out and he overnight mailed me a key.
They are truly wonderful vacations. Oh, and try not to do too much. After one hard working retreat, even with stops and chats, I was in terrible pain for a week getting over the bad chair, bad posture, too much repetitive motion while sewing a whole quilt of paper pieced string blocks. Never again will I work so hard and so long.