u/CarpinDies

I've decided to dive into sewing machine repair to handle mine and my friend's troubleshoots, and considered eventually asking around to see if I could do some part time work fixing machines at the local shops. Having worked construction most of my life, I'm pretty good with tools, but I was privileged to have company tools. So other than the flat head, brushes, and tweezer I've tackled these jobs with so far, what tools should I look into having handy? Multimeter? Stethoscope?

What are y'all using?

Thanks in advance!