Sewing machine repairmen used to come to your house...at least they did in my town. There was a Singer shop here until probably the mid 70s...& the owner/mechanic did "house calls". And there were also a couple independent sewing machine guys that did, too. One of the independent guys came to my house in the late 60s adjust the buttonhole cutting width on my machine. It looked simple enough...so I started working on my own machines!