As mikeef states, a Marriott hotel is obligated to follow the rules and they normally will do so. But that doesn't mean an employee at a particular hotel won't try to get out of paying the guarantee. They may try and state that they don't know anything about such a guarantee or that it doesn't apply to them or any number of "outs". I stayed at an RI the other night and they didn't give me a Plat arrival gift. When I went to the front desk, the person there tried to say that I had told them I wanted the 200 pts. But we never had that coversation. Given that I had my kids with me, all I really wanted was the cookies and water. So I didn't push for the cash guarantee, I just asked that they get me the gift (which they finally did.) So it always helps to go in knowing the rules and having any needed documentation with you. It gets really hard to argue about a MR# in a reservation when I have a printed reservation showing my MR# in the reservation.