Yep, it isn't a missed opportunity - bloody annoying though :)
The price of the heating system could have gone up after you got yours. Then you'd be writing a self congratulatory post extolling your excellent decision making skills and luck would not get a mention!
They might go up based on this and Covid. But I think they will not rise significantly.
If it weren't for bad luck, you'd have no luck at all
People say they have "zero luck" as if it is a bad thing - Neutral is okay if the alternative is negative :D