Originally Posted by sdsearch

While I don't know if this applies for Marriott, the main exception I seem to recall from some other hotel programs is if you book via a partner site. For example, since Marriott partners with Southwest airlines, it's possible that you might earn points if you book a Marriott stay through Southwest's website. (But I don't know for a fact whether you do or not.) But it still might depend whether it's a "clean" rate for the hotel seprately, or a package price.

IOTW, I doubt there's any 3rd party sites that do earn points and yet give discounts below what marriott.com does. There might at best be a limited number of sites you could use if you wanted to do your air, hotel, and car reservations all from the same site (ie, 3rd party site used for convenience, rather than for cost).

The only way to use random 3rd party sites to earn points is if you can use Marriott's "Look No Further" best rate guarantee. But this can be a little tricky. My first attempt failed because I misread the complex cancellation policy at the other site and didn't realize it was cancellable (and had booked the lowest rate on Marriott's site which was prepaid). My second attempt failed because I booked a prepaid rate on Marriott's site, and while the other site with the lower price was prepaid, I booked on the last day that prepaid rates were availble, and Marriott just waited enough hours for the prepaid rates to go away.

Now that I've learned from those failures, I can (at least temporarily and on some dates) find two hotels (among 20+) in one area where I can get Look No Further to work (for midweek stays, anyway), but at one hotel only if I book 8 or more days out with a prepaid rate (so the 24-hour LNF process will still see prepaid rates no matter how long they take), and at the other hotel only if I book 6 or fewer days out (once the prepaid rates have disappeared from Marriott's site), because the other website with lower rates has cancellable rates only. (And Marriott requires that the rate you booked on Marriott's site was the very lowest public rate -- prepaid or not -- shown there at the time you booked. And it requires that the room type and the terms be identical between the rate you booked and the 3rd part rate you're quoting.) So, as you can see, it can get kinda complicated. (It only worked out for me because I needed repeated stays at these hotels, and so it was ok that it took me a couple tries to learn how to make the LNF process at these particular hotels work for me.)

But one of the hotels, after I booked two separate LNF stays one right after the other (with a day gap between) last week, now this week the 3rd party site that used to show the better rates (that used for LNF) no longer shows that hotel (at least for the next few weeks)! So apparently LNF success can breed later LNF failure! So I'm not sure how much you can depend on LNF for often-repeated stays...