Is old PS Audio LAMBDA worth anything??

Unless it is very low hours I would not expect it to be reliable long term, and price should probably reflect that. It uses a CDM9 PRO transport which was very, very good in its day and one that some people still seek,

I owned a PS Audio Lambda Drive from the mid-late 1990s until about 2005 when it died. (Bad laser) I really liked it, but was unhappy at the relatively short life. (I did not play a lot of CDs in those days) The replacement laser didn't work and I sold it for very little money to someone I hoped would fix it.

There is a Lambda Drive on eBay right now at $720 which I think is a bit steep. I would put it on eBay as an auction with a fairly low minimum bid and see what you get. Audiogon might be another place to sell it, they may have pricing guidance for it.