Do you contract pilot's if on a multi-day trip, have your hotel paid for on the trip? Or is this not allowed under Part 91? Reason I ask is because I don't know what expenses are allowed to be paid for by the aircraft owner/person you are flying for.

Thank you!

The owner pays for, or reimburses, everything.
Everything withing reason.

If you're exercising the priviledges of your commercial/ATP certificate, there's no 61.113(c) type of expense sharing neccessary, if that's what you're getting at.

Keep receipts and bill for everything. Hotel, transportation, food, day rate, etc.