My guarantor owns a property, but doesn't live there.
That's fine. Your guarantor doesn't have to live in their own home; in fact, they don't even have to be a homeowner, but they are more likely to be accepted as your guarantor if they do.
Your guarantor needs to be 18-75, with a good credit history. They agree to pay the loan back if you don’t, so it's important that they can afford the monthly payments whilst having enough money to live their normal life.