I'm a huge fan of Club Carlson because its so easy to get free nights.

1000 points just for booking online
20 points/$ at hotels

A top tier night costs 50k points.


Additionally, once you hit the elite tiers as you continually stay, you'll earn bonus points!

Assuming about 90 days at $90/day, that's at minimum 162000 points which is three free top tier nights. Even more once you factor in booking bonuses and elite status you might earn along the way!