Should I leave things alone and just chalk it up to a lesson learned?

When we budgeted for our house we established the HVAC budget based on an average of the high and low prices that the builder's HVAC sub gave. We set this as an allowance because I wanted to involved in the selection process of the equipment and features of the system. We were sill making change to floor plans, ceiling heights, and insulation so it was not unusual to have this setup as an allowance. We did not have exact specifications but we did estalish a set of desire features.

We start construction and my builder kept the move going very quickly but had really poor co mmunication with us as the homeowner. I could go on and on about it but let's just say after the framing stage he disappeared on us and only came back around punch list time.

During the process I tried to setup a time to meet with the HVAC sub but I never got a response from the builder. At the end while going through the punch list we asked what was the HVAC system that was installed? He finally got me in touch with his sub.

Here is what happened

We paid for a change order early on to go full open cell foam on the house. When that happened the HVAC had to have mechanical air ventilation and a 98% efficiency furnace. This also reduced the number of AC units to one. We also added 2 gas tankless water heaters. The furnace, ventilation, and the water heaters were all extra costs that were not envisioned originally by the builder because we were not doing full foam at that time.

My HVAC sub in an effort to stay in budget put in a simple 13 SEER unit instead of the 16 SEER, variable speed, and zoned unit.

At the end of the day I was $800 under the HVAC allowance but I didn't get the 16 seer system that I originally wanted. I would have paid extra for it. If I change it now I would have to pay for the new system and the wrong one.

I'm a little concerned because I wanted to focus on efficiency since I plan to live here for a long time. Should I pony up the money to change it or am I making a bigger issue out of it than it really is. We are in the Dallas,tx area.

If my builder had just communicated with me, this would not have happened. Or if he had just been involved in the decisions his sub was making,. He did stay in budget but it doesn't feel like he did me any favors.

What do you think?