I’d first ask what “a gap” means. A missing invoice and several years of missing engine records would leave me with very different questions. I’d want the seller to explain exactly what’s missing before going any further.
Same, although I’d want an independent inspector to assess the explanation and any supporting records. A convincing story from the seller wouldn’t settle it for me.
I think I’d be less comfortable taking that on for a first purchase. Even if the price looked attractive, I’d want to understand the time and cost of resolving the missing information.
Would your answer change for a rare aircraft where there aren’t many alternatives?