Pricing and Caring for Old Typewriters
 

There are no catalogues or price guides for old typewriters such as those you'll find updated annually for postcards and stamps, coins and ceramics.  There simply aren't enough typewriter collectors, or typewriters, to warrant special listings.  Value, like many low volume collectibles is best determined at auction, and is the point where the price someone is willing to pay matches what the current owner will accept.  By far the highest prices are paid for typewriters in good, clean, working condition, with or without restoration work.

You should clean typewriters carefully, getting right into the tiniest of grooves without causing damage to keys which were often long and spindly and unexpectedly delicate.  I found the most comprehensive guide to cleaning old typewriters at: http://staff.xu.edu/~polt/typewriters/tw-restoration.html

Here's just a tiny few of their suggestions:

'A toothbrush and a nail brush can be helpful.

For a gentler initial cleaning on a basically clean machine, try Endust or Pledge (be cautious around decals (transfers), as occasionally these products can harm them).

For an even gentler and safer cleaning, simply use a few drops of dishwashing liquid dissolved in water.
Q-tips (similar to cotton buds) are very nice for cleaning hard-to-reach areas.

For initial dust removal, the vacuum-cleaner hose attachment kits sold in computer and computer supply stores and catalogues work very well!