There were very exceptional piano makers from Europe and North America like Steinway, Baldwin, Knabe, Mason & Hamlin, Heintzman, Bechstein, and other manufacturers, which by virtue of their well deserved reputation would usually be good candidates for restoration.

There were however many other piano makers long since gone, whose pianos are well worth an investment.

In addition, even a reputable manufacturer makes models of varying quality so, a very good name may in a certain year, may be on a less than good piano, or a once great instrument may have aged so poorly, that is an impractical project to bring back.

In the end each piano has to be judged on its own merits, but a well known manufacturer is a good place to start.