We get these inquiries from owners a number of times everyday it seems. The answer, as Denise said, is that it NEVER EVER is a good plan to pay so much as a $1 - not to mention hundreds or thousands - to ANYONE that solicits YOU and wants money to sell, transfer, rent or advertise your timeshare prior to you getting paid by the buyer/renter/transferee. If they want even a dollar then the chances are extremely good they are after the upfront money only and have no way/plan to actually sell/rent/transfer your timeshare to a new owner.
DO NOT try to deal with them is the consistent and best advice we can offer to all who ask. Far too many don't take that advice and lose whatever money they decide to risk. Don't do it. Handle the sale/rental/transfer of any timeshare you are done with yourself to assure that you don't get ripped off or worse.