We recently did this by negotiating directly with the hotel. We were Marriott members, but the local Hilton property offered us a better deal for a 3 to 6 months Stay.
When we did speak with the general manager, she was on a first name basis with the competing hotel manager , so their deals were similar. Also find out the rules, but we learned that in our neck of the woods if we stayed 90 consecutive days, the hotel taxes did not apply.
Lastly, on day one I got the hotels credit card and racked up nearly 960k pts. Made sense.