If you are looking for a Treadle Sewing machine....here are a few suggestions I think might be helpful.
Complete as possible with attachments is a big plus...bring a smart phone or look up what you find on your computer to check average prices, attachment availability etc....on ebay, CL or etsy.
Turning the wheel by hand with a needle in it plus fabric to check that it advances easily, even if there is not thread on it.
If there is a belt on it, pressing the pedal down to see if it turns the sewing machine. Without prior experience fixing one, I would want it to advance. If no belt, rig one up to check it.
Check for the bobbin winder as those are important to have! Mine is a separate one that attaches to the sewing machine.
Besides the attachments, needles and bobbins are important items.
However, I have to say, for my 1891 New Domestic I found old stock needles on ebay. Mine came with 14 bobbins but I saw ones for sale so they are available. Just go onto ebay or etsy with the one you are looking at and see what is available for it.
Decide prior to your going to see one how much work you are willing to do for it. If you stick with Singer or a popular name brand, parts will be that much easier to find also.
Have fun and don't be in a hurry! You will find one for what you want to pay for it.
