But not all management companies will treat the lock off the same way...most do, as Alan mentioned.
So, you have a L/O unit at Marriott. It is a very desireable week, and Interval would love to have it.....so much so that:
You L/O the unit after you have reserved the best possible week in your float period-both through Marriott....not Interval. (And there is a charge)
OK...you now have two great units at a great bright RED time. You now let II know what you have. If they are in need, they may give you a bonus or Accomodation week (week with restrictions) for your one full bedroom side.
Restrictions include a fee, must be used in a year, and sometimes no trade back to your home resort.
So...from your one week and its related maintance fees....you ended up with htree weeks.
If Alans' week (a three bedroom that can L/O-and configured correctly) is managed by a similiar contract rules, he might be able to get 4 weeks from his one....but that is real rare..but has been reported on the TUG.
This doesn't work with most resorts that trade with points....because the week you own has a specific number of points....but in off times, a resort will 'cost' less points....and this will just confuse, as you list a Marriott...and they aren't really a points program yet.