These are good people to talk to. They are down there in the trenches and they deal with who lives there every day.
There are so many things that can go wrong and so many hidden costs.
There have been thousands of dollars wasted in blueprints and plans because some neophyte developer hired an architect who spent tons of time and money drawing up plans (that were ultimately rejected).
Without zoning approval, you're toast. That's the first thing you have to look at.
Ask him who was the best client he ever worked for and why and who was the worst and why, ... Your profile might match that description (indicating the arrangement might not work out.)
You don't have to be a construction expert. But you do need a reasonable level of education to know if the job is being done right.
It's the old real estate mantra: location, location, location.
If we could translate, I'm sure it would be bat profanity.
You have to have deep pockets and you better have experience. I don't want to extinguish anyone's entrepreneurial spirit, but you should really start small.