Looking for people with experience on HVAC for interviews

Hello
i am evaluating a HVAC business in Ohio focused on commercial space. I would like to discuss with people
working in this space or having made acquisition in this space. I am open to partner with other investors in a roll-up strategy.

As I am preparing my LOi I would like to discuss to someone about the following g
- competition for acquisition of small HVAC business and multiple for $0.5 Million EBITDA and some key-man risks
- long term trend for PE acquisition of HVAC
- differences between commercial Vs residential (Margin, models…)
- typical function and organization of HVAC teams (engineering, installation, maintenance, trucks…)
- typical synergies in roll-up
- any advice