A friend has just bought a flat with a balcony. Flat is in good order, the seller left it clean and nice but the key for the door to the balcony is missing and the door is locked so it will need a locksmith to fix it. Friend says she will demand the seller pays this cost, I say it's not worth hassle and, as the seller now has her money, it's going to be very hard to get it anyway (especially as friend got a bargain in the first place). Thoughts?