Here are a few things to look for in a hand grinder, in my opinion:
1. Stepless grind adjustment - absolute must - avoid the kinds with a four-notched wheel adjustment on the axle - the notches are steps, and it will be more difficult to set the correct grind. Some have adjusters inside the drawer, some on the back, some on the axel on top (the newer Zasses).
2. Ask the seller if the burrs appear sharp and rust-free - better yet, ask them to grind a few beans at the finest setting to see if they look even and fine enough for "turkish" coffee
3. Ask if the edges on the burrs look cast or machined -the machined burrs have sharp edges like the ones in the photos above. Some of the old German grinders say "forged" or "stahlmahlwerk".
Purchase of a used hand grinder can't be risk-free unless the seller has used it for espresso. Even then, they may not measure up to a Titan:
I've asked Jim S. to compare an old hand grinder to the Titans just to see how it fares, and I'll ask him to post his impressions here soon.