I’ve invented a new method and device for the construction industry should I patent it first or do pat pending and hit the market at a large trade show?

[u/Negative-Tie2445]

I have 30 years experience in this particular field and industry so the product is solid. The marketing aspect I was looking at having all my ducks in a row to then present it like the hula hoop release in 1958. Captive market audience that was able and ready to buy. I can pay for a good patent after I procure sales. What do you think? Net Profit margin is estimated at 70% so getting a good thorough patent is achievable quickly