Hello, Wiltshire. There are in fact a number of buildings that offer fairly flexible rental restrictions. The Flamingo for instance allows you to rent once a month. Most condotels (condo-hotels) offer plans for you to not have to concern yourself with any details and rent even daily. Of course, there are others with more restricted rental policies like up to 2 times a year or just once a year and fewer still that allow no rentals at all.
These come in all price ranges, locations, amenities, etc. Be mindful however, that depending on the number of times you rent the unit, you may be subject to taxes (including sales tax, hotel tax, income tax and others), so you should consult a tax advisor before making your final decision.
Hope you find what you're looking for soon. :-)