Buying classic equipment to use? Don't buy mint!
This may sound a little counterintuitive but I’d never recommend buying classic equipment in like-new condition if you are planning to use ‘in anger’.
You’ll always pay a premium for mint equipment. However careful you are, there’s always a chance you’ll scratch the base or the strap will rub the camera's corners. And that could potentially knock £100s off the camera’s value (especially if it’s Leica!)
Also, you’ll find that seldom-used equipment is mechanically less sound than equipment that has been regularly worked. Often, a camera that’s carefully and constantly used will be  ‘run in’ and feel silky smooth. Ironically, a 60-year-old Leica M3 in like-new condition will feel rough in comparison!
Buy yourself a clean (but not tatty) example. You’ll enjoy it more and feel relaxed knowing the odd slight rub or ding won’t matter.