Custom Services Tulsa Heating Air and Plumbing

So I had a new unit put in in Fall 21 by Custom they quoted me 19800 for a full new install including modification of returns and ducts in the middle of the job they say Sorry we can't move return because roof is to low and then we were told the return had a 1/3 blocked but it shouldn't be a big deal then when we asked for static test they wouldnt supply it and told us they were sold to the same company as Airco Mullin Air assurance etc.. and they would take over and still to this day I have a return 1/3 blocked with no static test report from a over 19000 dollar sale on a 2100 sq ft I story house and they told me I'm out of luck because the company i purchased it from doesnt exist even when Airco has been servicing and working with us from the 2nd week in( because yes this installation turned into a 3 week ordeal ) Nobody would stand behind their installation work. They even acknowledge that it is blocked and not installed to manufacturers recommendations so it would void my warranty according to Daiken along with no static pressure test. I have reached out to them for 3 years and they wont do anything unless I pay them more money. What happened is simple the job became more expensive because someone did not have foresight to see the complications in the modification of the return even when the quote explicitly states modification of return included in the 19000 dollar price from Custom. I also have the estimate from Airco on the same day that afternoon that had a Lennox system and all duct modification for 19000 as well. So I guess I'm stuck with a 3 year old unit with no warranty because I can't afford any more after the 19000 that was on the high end we could have gotten a cheaper version for 11000 that would have worked just as well because this unit can't work properly when 1/3 is blocked . So maybe they will see this and we can finally have resolution because I feel Scammed and this is the pinnacle example of Corporate greed.