Once fish are stocked, they will stick around whether you feed them or not. Typically enough natural food to keep a population present.

Sharing a pond with other people is the tough part, they usually have other plans than you do, or have crazy ideas that don't blend well with what you want to do.
There are a few stories about shared pond here, none of them are good ones that I remember.
Welcome to Pond Boss, my healthy escape from the day job.