Warranty:

Used items produced from and after 2010 have a 30-day warrenty against mechanical defects. We retain the right of either making a repair or making a refund in case of a mechanical defect that I did not detect myself.

For cameras and lenses produced before 2010, common sense should prevail.
One should assume that many of the items have seen little recent use and, therefore, have not recently been cleaned, lubricated, or adjusted.
This means that many items might have shutter speeds and/or light meters that might need adjusting, and that lenses and  other optical items might require lubrication and/or cleaning. We can not offer a warranty for these items which are essentially collector's items.

If the item is clearly not according the description, it may be returned for full credit within 10 days of receipt. If defects have  not been mentioned in the description, I will have it repaired at my expenses. If repair will not have a positive result, I will refund for the full amount. For mechanical defect on items that were produced after 2010  this period is extended to 30 days. Of course returned items must be in exactly the same condition when returned as they were when received by you. We do not refund any charges for shipping, handling, or insurance. Please  note that we can not accept any returns without our prior notice and approval.

So far I never had an unresolved disagreement with anyone; I always managed to find a satisfying solution whenever opinions are different. The client has the right to demand a second opinion of an independent third party (for example Leica Gmbh Germany or the Rollei representative "De Greef" in Holland).  I will comply with their opinion.

Of course I always use my knowledge to determine the originality of the equipment. I guarantee that all the equipment I sell, is original. In theory it is possible that I am the victim  of buying false equipment myself, while I sell this false equipment (without knowing the equipment is false) to customers. Rare and unusual collectors items are expensive.
For your protection I give warranty on originality for a period of 1 year !