Thanks guys. All useful. Its probably about 25 years old - I remember him getting it. Its hardly been used - he just likes to buy "nice" things!, but it seems likely to need all seals etc replacing (which I would expect) plus probably a professional CLA, because I don't think I could tackle an in-lens compur. Just being prepared in case the guy does decide to let it go - as I say I don't really need it - and not going to push him, but want to be aware in case I need to do a quick deal!