I think the OP had wanted to hear about free stuff that turned out to have a “hidden cost” perhaps making the free thing not quite so free…
In that vein, one of our research scientists called up from a vendor convention all excited that he’d gotten a great deal on a “floor model” of some processing equipment (if anyone cares, it was a twin-screw extruder of German manufacture). I don’t recall the exact numbers but it was along the lines of a $500,000 piece of gear for $150,000.
Got it back to Canada and was informed by accounting that we would need to pay various duties. Was informed by Engineering that the bulk of the wiring would need to be reworked in order to function on this side of the pond. Was informed by various safety agencies that pressure safety and electrical safety certification would need to be documented in house, from scratch (something that is quite time consuming and normally handled by the vendor, and hence built into their price.)
The unit ended up costing us 25% more than if we’d bought it brand new at list from the NA sales rep, and took 8 weeks longer to prepare than the longest delivery time quoted by the vendor.
They really tightened up on signing authority after that.