House had a slab leak in the past

[Bienes Raices]

I've found a house that's in very good shape except for the fact that it had a slab leak in the past. The owner and his contractor friend removed all the fixtures in the bathroom where the leak occurred and repaired the problem, so that bathroom needs to be completely redone. Apparently they also replaced the sewer line as well (not sure if that was related to the slab leak or a separate issue).

If there was one leak is it inevitable that there will be more? Should I go ahead with the offer? The house is 30 years old with copper pipes. Thanks.

I should add that the person has been living in the house (it's a short sale) so I would assume that the plumbing is functional at this point.