If they are Gypsies you won't have any trouble with them, My family are from gypsy stock so please don't start slagging them off, gypsies work hard and are very clean and honest,
If on the other hand they are just lazy sods that travel about the country pinching things, leaving crap,causing trouble and scrounging, kep your doors locked, anyway shouldn't you be keeping fir ready for a match or something? and I don't think the police will let them stay for long in such an affluent area as the one you live in, do you?