Depends on condition and how original it is tbh
There have been some 'mint' Egress's sold in the last couple of years that were Avante 2001's or Vanquishes with the carbon-chassis upgrade and stock Hi-Caps. A couple made good money - but to get them to proper Egress spec with worn/broken parts replaced as well wouldve taken a lot more money... Its amazing what silicone spray can do on a car when your selling it
The Avante was re-released not long back so some spares are cheaper now, and sooner or later the Egress will be re-released - probably like the Avante, with some new/uprated parts. But some people will always want the original, so dont worry too much.
As Rich says, prices can be anything that the collector is willing to pay, but with Egress's originality & condition is king.
Id go 80-100 for a 'Egressed' Vanquish or Avante 2001 in ok condition. Less if very worn. Good, original, Egress for the shelf, 200 odd, new-built one 300+. If its missing some Egress-specific parts but still good condition, 150 odd. If the bodyshell is in good condition and in box art - silver - then thats a big plus. Egress's with tatty bodies or not box art colours go for much less. You can get repro bodies & stickers still, but will cost you.
But it really is dependant on someone wants it or not. Although some spares are cheaper now due to the Avante re-release, they are slowly creeping up and some parts will cost you, if you can actually find them.
And dont even bother trying to race it against todays modern cars, it will a) break often and b) be lapped.... even more often !
Get some pics up though. Lets see what it is