Would ths beach bike be any good?

well only way to know is if u go see it in person but they dont look that bad. good price. i havent had a coaster brake but im sure there is a way to loosen it a bit for the wheel to spin freely

You don't want to loosen a coaster brake, unless you like the idea of your wheel locking up at 25mph and sending you flying to the pavement. A properly serviced and assembled coaster hub should have no problems spinning freely, motorized or not. There are only 3 things that will cause a coaster wheel to lock up on a motorbike. One, the clutch is not properly adjusted. Two, the sprocket bolts won't clear the brake arm. Three, the coaster hub was improperly assembled after the sprocket was installed, and either the wheel was locked immediately or after so many miles the bearings destructed and the wheel locked up.

I'd give $65 just for the red one myself, that looks like an older bike and either of them would be good to China Girl them.

Map

IMHO get a bike with front suspension.

Listen to mapbike and get the red one it looks older and most likely better steel than the green Huffy but get both if you can. Front suspension can always be added later.

And sticking with stock coaster hubs on newer cruisers is just asking for trouble. Get or have one built with a Shimano 110 or an old Bendix.