Our vendor has provided FENSA certificates for some of the window/door replacements in their property since 2002, but not for all of them. When asked for some kind of documentation regarding the other window/door replacements (we know there have been more), they responded saying they have provided all available paperwork.
Note that we checked the property address on the FENSA website, and the only certificates available are the ones they provided us with.
How big a deal is this? What should we do? We believe it relates to a relatively small number of windows/doors, so it's not like it's the whole property.