u/thrownawaybaseball

Two of our second floor bedrooms (both have 2 exterior walls and share one interior wall) are always way colder than the rest of the house in winter and way hotter in summer. House was built in the 1970s.

In researching, it seems like there are so many things that COULD be the issue, but I can't figure out how to determine what's the best thing to try. No clue where to start and would love to not waste time and money on things that won't help, or trying to figure out what's the most likely issue so I can try that solution first. What's the best plan of attack?

Add attic insulation?
Replace old windows?
Seal HVAC ductwork?
Exterior wall insulation?
All of the above?

I've been searching for years for this short comedy video and song but cannot find it any more. My wife and I can both sing it and remember the tune and some of the lyrics, but can't remember the video part of it.

What we can remember:
Song is short, like 20 seconds max
Male vocalist
Not much instrumentation, maybe just a single guitar
Lyrics that we can remember: "I wanna Buttchug your fluids" and ends with "if I say I'm sober it's a lie."