maybe not, but you own the house, or rent that house or apartment, so it's YOUR RULES. if he cannot respect your property, it's time to forbid him to visit.
you gotta put your foot down, or up his........
Well said,every man's house is his castle,just because he is related doesn't give him reason to treat your things like they are toys,they are in your house because you want them there,worked hard to pay for them and treat them properly.As for fingerprint acid only have to look at fingerprints on glass to realise fingers leave chemicals on surfaces,use your phone enough then see marks all over the screen