Castagnari made my primary button box. My backup instrument is an Accordiola, assembled in Belgium.
My cittern is a Stephan Sobell
My main workhorse mandolin is a Flatiron A model, signed by Bruce Weber, who now runs Weber Mandolins
Martin made my D35
Gibson made my mandolin, my mandocello, my mando bass (before they went over to the Dark Side...)
My favorite hommel (GDDD)was made by Gerrit Van den Dries from Tielt (BE). I also have on in C made in Hungary.
my regular stringed instruments repair guy is Steve Carmody from Silver Spring. Recently Marc Glickman from Frederick has been doing some amazing restauration work on my mandocello and on my Dyer. See the before and after pictures!
I've also had work done on my mandolins by Ward Elliott in VA, excellent!
I'm very satisfied with the work of the Button Box in Amherst. On the other hand, as much I would love to have a local guy for accordion tuning and repair, I can not endorse "Ike" of of G. I. Milligan's Nationwide Accordion Repair Boxpital. He claims to be "by some, considered the best accordion tuner in America." I've had the worst experience with him!