OP - basic rule for buying a house is - location, location location.
It doesn't matter if it is small, or if there it needs decorating etc, if it is big enough for him, and gets hima step on the housing ladder, great. My brother bought the tiniest 1 up 1 down you have ever seen when he was 19. It was the best thing he ever did.
BUT it has to be resellable. Location matters, if you can't resell it, it is not an investment. Doesn't really matter if it isn;t the best area of town, it just matters if people are buying. If it is in a down at heel area that people are happy to live in and the houses trun over steadily, fine. if it is in a rough area and no-one will touch it with a barge pole. Then don't touch it!