Why would the HVAC company want to stop subbing work out but not hire a lic electrician except to save money by cheating taxes, insurance, and risk? Sounds like they want to pay like your an employee but treat you like a sub.
If you want to work for them tell em $xx per hour or week paid as an employee whith the same benifits as the other HVAC workers (like helth care, workers comp, unemployeement, paid vacation, paid sick days, bonous, or retirement. Maybe even a Co truck with material stock, fuel and equipment. If you can find your own work then tell the HVAC Co you can provide electrical job leads for his Co but you want a small percentage of $$ from the work done from that customer. My guess is they wont go for any of this because they don't want an employee they want a sucker.
Starting a seperate business as a partnership with the HVAC owner would be dumb. If you owned only 1/2 the electrical business (give or take) 1/2 the money you earned after the bills are paid would go into the other persons pocket. You would still have overhead and insurance.
Some sample math to show what would happen.
Labor Rate $75/hour.
O/H $35/hour
For each hour you clock you only get $20/hr
$75-35=$40 $40/2=$20 Per hour each
That $20 per hr probibly would not pay for estimates, desk time, phone time, material handeling, cleaning / fixing truck, etc..
If you manage to spend 75% of your time on a paying job in 40 hours you whould bring home $600 before taxes ($15/hour).
If we just charge more say $115 per hour you would bring home $30 / hour with the above numbers. Remember the HVAC owner is also making the same $30 an hour for your work.
Also conciter confilcts of intrest. Such as inflating the overhead of the shared electric business to cover the costs on the HVAC biz. It may be the same office, utilities, or even the person that answers the phone. Also is the HVAC owner going to want to pay $115 / hr to his other company so you can make a living? I sure HVAC guy would want a discount rate for his HVAC electric work. Maybe just a bit over cost so you do HVAC work for almost free.
Tom