My BSH is an indoor cat, I've let him into our enclosed garden a few times in summer months but he's generally there because I am.. if I go inside and close the door he scratches to get in right away. The breeder asked I keep him indoors and I was happy to do so but after a year I let him out but he's just happy following me around so I don't feel guilty about him being indoors. Advice would be get a hooded litter tray, get them neutered, regular grooming , access to scratch board and toys. Love British shorthairs they are really laid back companions and he's been great since my son came along too.