Backyard vs. apartment

My lhasa apso/shih tzu is 12 yrs. old (13 in June). He lives with my parents who have a big backyard that he is used to. He sleeps in the garage at night and has free access to the yard all day. I don't particularly like the food they feed him (whatever's on sale, no regard to dietary needs or age). He is a good weight, but that doesn't mean he gets proper nutrition. I also don't really like the care they provide (feedings, letting him out in the morning, not much physical contact). I see him almost everyday at my lunch breaks and play with him (or just walk around the yard with him depending on what he feels like doing). I clean out his bowls, because otherwise they wouldn't be cleaned. My parents would just put food in a dirty bowl. He has chronic ear infections and only gets vet care when I take him. I want to take him to my apartment to live with me so I can give him what I think will be the best care, but I'm afraid he will hate it. Any advice on moving an older dog from a big backyard to an apartment? I'm grappling with big yard and so-so care, or smaller space and finer care.