Hand me down tip #1
Use a binding that is easy to adjust to a wide range of boots.
Most fixed bindings will adjust +/- 10mm, or about one shell size. However the boot will not be perfectly centered on the ski. Often the owner ends up paying to have the ski remounted.
The Tyrolia Railflex offers practically unlimited range in boot size and placement without remounting. Adjusting the binding, to a new boot is easy enough to do at home if the owner understands how to set the forward pressure. The best part is the ski binding can be reset an infinite number of times, no re-drilling. Volkl Motion systems offer similar flexibility.
Many of the plate bindings can also be reset multiple time since the ski is not damaged by drilling. Some Atomic, Rossignol, Dynastar, Elan and others can be adjusted or remounted as many times as needed.
Avoid mounting a binding toe and heal directly on a flat ski. Use the Railflex of another type of binding that has a plate that can be refitted easily.
Hope that helps.