Monopoly Deal Cards - What happens if you don't have enough cash and only a property set made with a property wild card on the table?

If you don't have any cash in your bank and the only property you have on the table is a full set - one brown property and one wild card. Someone charges you 10 million rent. How do you pay?

Do you only give your one brown property to make your payment? Or do you give the whole set?