I am building a SaaS product for businesses and I haven't formed a legal entity yet. Some people have advised me to gain traction monetarily before I incorporate a company and the main reason they are giving is that investors will only invest if the startup age isn't greater than 2 years and waiting until getting investment will also reduce the mandatory regulatory expenses until you get the investment after which it can be handled by the investor's teams or from the money you get.

On the other hand, some have advised me that a customer or business will only pay you if you have a legal entity with tax credentials.

I don't know what to do. And I am still building the MVP and haven't launched yet but have customers who are willing to jump in on it after I launch.

What should I do ? and thanks in advance !