I had to have this for the water this summer! The kids are going to have a blast with this. We just grabbed the Rescue Squad Inflatable Boat with Water Squirter from Costco.ca for $69.99 including shipping - Toys R Us has the same one for $84.99 plus around $20 for shipping (with a $10 discount).
I am going to tether this thing to the dock and consider it a way to keep my kid busy while I sip a cold bevvie standing in the refreshing water beside him. The Rescue Squad Inflatable Boat with Water Squirter is even large enough for two young children and the squirt gun uses water from the pool, so you don't have to worry about refilling it!
It can even hold up to 180 lbs - so if you need to hop on board for some odd reason (water guns are fun!), then you can. It is best suited for kids ages 3 and up, and of course always supervise the kiddos when it comes to pool play.
Costco.ca throws in free shipping and handling with no minimum purchase.