I have my Mom's Singer 306 W ( circa 1950's), it really is a work horse. The amount of hours that have been put on that machine , even prior to me getting was HUGE. My mom made all our clothes, coats, pinch pleat drapes etc. I think when I got the machine I also got a bit of her sewing skills.
Its amazing this older work horses can be gotten for $25 - $75 Dollars at garage sales , goodwill. My local dealer (sew/vac) just about gives them away when they come in on trade.