Any bike in line=new condition for $55 is a good deal.

What year? if it is an old-scholl rigid MTB from the late 19190's that is a super score. Tons of fun, go almost anywhere, do almost anything, can be set up for street or trail or dense woods for anything except flight and oceanic voyages. Fairly simple and nearly indestructible.

I think later models and more modern ones might have a front shock .... but if it is "like new" condition, no problem.

And for $55---I might pay that for a bike which needed maintenance and repair just to get the chromoly frame.