Buying a property without building regulation approval for bespoke wooden double-glazed windows, bad idea?

[Pumpkinsandhotchocolate]

Hi, we are currently close to the exchange on a 300 year old property in a conservation area. We have found out that the sellers don't have a FENSA Certificate or building regulation approval for the complete installation of double-glazed bespoke wooden windows they had installed after April 2002 (when the building regulation requirements were introduced).

We would like them to get a retrospective building regulation compliance certificate, but we think this unlikely as it can take up to 8 weeks and they are pushing to exchange ASAP.

The other option is indemnity insurance, but this seems to only cover the cost of having to have the windows taken out and re-installed, and not the cost of any fines (which can be limitless) from the council, which seems like a huge risk to take.

Does anyone have any similar experience/advice?

When were the windows installed?

In the last 10 years

The other option is indemnity insurance, but this seems to only cover the cost of having to have the windows taken out and re-installed, and not the cost of any fines (which can be limitless) from the council, which seems like a huge risk to take.

It's the other way around, indemnity insurance would cover legal costs and whatnot, not the actual costs of works required.