We have a early 80's house with aluminum double pane windows that were all failing due to age and fogging up internally.
Rather than replacing the entire window we had a local company come out and replace the glass with new "sealed glass units" and saved a huge amount compared to the replacement bids we had, like 1/3 of the cost.
Now to the DIY part, while they replaced the glass in the windows they didn't replace the old weather-stripping on the frames. It took a hot minute, but I finally found the right replacement using the keyword "window pile weather strip" the size and dimension is dependent on the windows but 100' rolls were inexpensive and it only took an afternoon to replace it on all the windows. It's probably my imagination but I think it made a difference, the 40 year old felt was quite worn on many of the units.
