If it's a potential 7-figure deal - go find a good merger and acquisition (M&A) attorney, it will be WELL worth your time and money. If you end up going through with the deal, you want to make sure you don't make reps and warranties that could damage you in the future. I've been through 2 acquisitions as a founder, once through a competitor. Part of any legitimate inquiry besides "just talk" is a term sheet. If this term sheet isn't under the NDA - you could shop it around a bit. They want you. The person that is willing to walk away has all the power. Definitely be skeptical at first - they have nothing to waste but time until the deal is signed. Don't be annoying when talking with them, but don't give away "trade secrets" - it's hard to advise without knowing the context of the business - but I'll try my best.

This is getting more into the valuation side, but if the multiple you speak of is based on 8x EBITDA because of some sort of recurring revenue/profit, then you could find investors elsewhere (easy). If it's based on an IP valuation and you are a company in debt and not making money, that's a different story. Just the fact that someone is interested in acquiring you (whether it's just a fishing expedition or legitimate) will bring confidence to other investors. Regardless, it's a personal decision. I always think of it like this - if you were to not take the deal, and your company went bankrupt in 2 years, or you did take the deal and your company grew 10x in 2 years - which would you rather do? If you are not ready to sell your company, then don't do it. In my last company, we got 3 potential buyers before we sold - everyone wants to buy a successful company (especially now that so much capital has been pulled out of the markets).

Regardless - congratulations. Whether this is fishing or real, it's a great milestone to reach - so be excited about it.