Prices for pool parties can be found on the pools website / the towns website. It will range from $130 to $190 depending on if you are a resident of Cheshire and if you already have a existing pass or not. There is up to $60 extra for "organized games" depending on the number of children. http://www.cheshirect.org/recreation-and-leisure/community-pool#birthday%20party
You cannot rent the whole pool, but a birthday party can be around $150, I'm not 100% sure though...
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