I'm no expert, but some people, like me, paid a lot to buy live rock and sand, which is what you have now.
I'd vacuum the sand, remove water like you're doing a water change, but save it in a brute, put the live rock in the brute, plan it all out so you can get the tank from A to B, and get it set back up with little to no die off.
Unless the tank is currently in bad shape, personally, I'd be trying to save as much as I can, but I do believe vacuuming the sand, thoroughly, is a solid idea. Rinsing it, and likely killing most of the beneficial bacteria though, seems unnecessary.
Again, I'm not an expert, still learning, but this is what I'd do.