I'm selling a 16" Meade Starfinder dobsonian tube, base, mirror board, focuser and finder, for $150, local pickup only.
There is no primary mirror, mirror cell, secondary or spider included. Purchaser can also buy the 4" secondary and spider for $100 more.
I have a Meade DS-16 equatorial and was using the mirror/cell/board from that in the dob tube occasionally, but I guess I don't really need to keep both.
You could always install a smaller mirror in this now, and upgrade later!
Not sure if you could squeeze a 17.5" mirror in the tube, though, but I think the outside diameter is about 19".
Thanks for looking!