Do surveys and potential user interviews count? Does first hand knowledge of the problem count?
Hi! First of all I recommend to make a pitch deck for yourself that completely describes your product, user needs, market and theirs validation and lay down money after you will be confident with that document on proof of concept (it will cost you much less then creating MVP).
I'd be happy to talk further with you about the difference between MVP and proof of concept stages and help you to set correct KPI to each of them regarding your product
