Not that im aware of. There are different facilities depending on where you park though that may be willing to help, such as the library.
I actually bought a dry bag from REI for $8 and put my remote key inside a plastic bag inside of the dry bag.
No, there is not. Hide everything in a car and use spare car key to lock and unlock. Spare key usually has no transponder or remote, so not a problem if its in water.
I'm not aware of anything like that unless the tube rental places offer that.
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