Here's a budget tip for you that may work for some.
We used our in-the-fridge pitcher from home for 2 weeks there. We drove down so wasn't a problem packing it dry with other items inside. Every evening & morning someone was assigned the Water Bottle job. We put all our normal bottles we usually use with their thermal "coats" & straps for carrying on a counter. Designated person filled them half-full with Brita water from pitcher in little fridge. As there were 6 of us the pitcher did have to be refilled during this process. All half-filled bottles into freezer if we had one at the hotel/condo that night.
Next morning, designated person fills up rest of bottle with cold Brita pitcher water. And we're off.
I really thought I'd be buying the Brita bottles for each of us before we went, but then the idea of x 6 AND always getting filters for them in the future (different from our usual Brita ones) didn't make as much sense as just using the one we had!
Of course, we did go during what turned out to be a quite cool Dec - January so refills during day weren't an issue. But if you are planning on mid-day hotel breaks with tired little ones it would still work.