[RWebb]

I have 4 nasty little vinyl sliding windows I want to replace with IGUs (Integrated Glass panels). All 4 of them are about 12" high; 2 are 27 wide and 2 are 44" wide. These slot windows are nasty little sliders that do nothing for ventilation, are hard to slide, and make a great place for mold to grow and for spiders to hide.

These things are mounted low below 2 big picture windows downstairs.
I thought about having somebody pull the entire 2 units out of the
wall (1 big + 2 sliders in each unit) and put in 2 full windows, but that costs $3,000, so I am going to invest my labor in it and save some bucks.

Now, to do a good job and seal these thing right, what do I need to do?

[1] I think there is some kind of dense foam that you put on the bottom of the rough opening which they sit on (?) What is that stuff called?

[2] Also, there is a tape that goes on the exterior and seals against air leaks - it is some special tape but again I dunno the name of it?

[3] Any other thoughts? or things I am forgetting?