Just to put forward the other side of the argument… I also live in an old building that has windows that shake when it’s windy and aren’t overly insulated. Cold in winter, hot in summer. However it was cheaper to buy into an old building than a new one, and it was all I could afford so I made the compromise knowing what I bought.
Do you think maybe the other owners are in a similar position and won’t be able to afford the increase in strata fees to replace all the windows? It is not a cheap exercise at all… as you would be somewhat aware since you’ve found out the cost of double glazing (not saying it would be that much, but certainly not cheap). The other owners may have bought in willing to compromise on the quality of the windows for the price.
They don’t sound like they are leaking so I don’t think you can say they aren’t ”functioning” even if their quality is not ideal.
I went to bunnings and got foam weather strips and installed them around all my windows which helped immensely… and cost $30… maybe look into some other options that can help?
Also I’m pretty sure we still have 2 years to do the locks… that’s what our strata manager told us anyway. (I’m in NSW)