I do expert work all the time. Form an LLC have a masters or two and a PhD with some published work then people will call you to court as an expert or as a consultant to well consult investor’s or project managers or stock holders. It’s a sweet gig my hourly rates start at $175, $250 if I’m away from my cush home and former model 3rd wife :)
When dealing with lawyers, always get a cashier’s check in advance.
If case is settled before your expert testimony, return half.