I'm not a fan of Naxos, myself - and I agree with the others recommending fewer of a better quality.
However, there are bargains - even better than Naxos - so here's a webpage you may be interested in:
http://www.classicalnotes.net/columns/cheapweb.html
Also - before making any purchases try to ascertain whether your father in law is more interested in large scale orchestral (which is what most of the RCA's are) or smaller scale chamber music like quartets, sonatas, and solo performances. Some people really prefer one over the other.
However, there are bargains - even better than Naxos - so here's a webpage you may be interested in:
http://www.classicalnotes.net/columns/cheapweb.html
Also - before making any purchases try to ascertain whether your father in law is more interested in large scale orchestral (which is what most of the RCA's are) or smaller scale chamber music like quartets, sonatas, and solo performances. Some people really prefer one over the other.