I’ve been and hvac contractor for 37 years and did 4-5 houses a year for personal friends. I always dealt with the homeowner except on a few and never took a draw but I wanted my entire payment on the final inspection. I did my last new construction on my daughter’s house and finished it in may
And it will take someone special for me to do another total new one. Best best is finding a good builder who has good subs that pay their bills quickly.
Or if building your own is find someone who has done it a long time and pay them a premium price for their work so they will be there for you in the future. HVAC equipment is up 136% more now than in January of 2020 and the materials to do it are also up about that. Best bang for the buck now is find a place or property you like and remake it into what you want it to be. New builds are just not worth it in my opinion.