Tulum is fantastic! Such beautiful beaches and a world of difference from the chaos of Cancun.
You can spend good money for beach side accommodations or, IMO look for some of the really cute and very comfortable places in town and then rent a bike to get to the beach. There are far better food options in town and it's a nice ride each morning.
I went there 2 years in a row - about 5 or 6 years ago - and there was a "kite club" towards the eastern edge of the beach which would also allow you to store your gear there for a small fee each night.
Assuming you're "normal" weight bring a 10, 12 and a light wind kite as my experience was that I was on the 12 most often but there were certainly days that it kicked up and there were others that it was quite light. Nice reef on the outside for some waves and smoother water inside.
If you're there, be sure to look up Marco Christophenelli (I'm sure I spelt that wrong) from
Extreme Control. He's a hell of a nice guy who can talk in Spanish, English and Italian and often just rambles in all 3 at all times. He really is a fantastic guy to hang out with though, hilarious. He'll make sure you have a great time while you're there.