It would only have been around $200 when new so probably not worth spending too much on. Why not just try it out and see how it works?
Run some water into a glass and see how it comes out i.e nice and clean or full of muck?
Rubber seals can deteriorate with time so check for leaks e.g. does water drip from the steam wand? If you cant get a good seal at the group when pouring a shot it may just need a new group gasket which should only be $10-15
As with any machine you will need freshly roasted and freshly ground coffee for best results.