I bought 2 of them to replace at my house when we moved in. They had the original ones (wooden) from the build (1987). Got them off Amazon; aluminum ones.
2nd the effect of lag screws (1/4" x 3"). You'll use a flexible strap to hang it temporarily, I used sheetrock screws, then come back with lag screws. You'll use 14 of them around the border. The ladder has lots of holes at the bottom to allow for getting the length just right. For both of them, I did have to cut some of the metal off the 2nd folding part; the 3rd part is the finished foot part. You can use a hacksaw or recip saw. Hacksaw just takes a while.
The first one took me about 3 hours total to get it installed and operational. Took another hour or so to put the trim back in; I haven't finished it fully, as it in the garage. The 2nd one took me about 1.5-2 hours to install and about 3 hours to finish up. This is in the house (kids' room) and needed to be finished. I painted it (after finally finding matching paint from the previous owners) and it was done.
It is a 2 person job, but only for the actually raising and temporarily installing it. After that, single man job. One other bit needed was wood spacers. The older system was wider than my new one, even though the new one has a bigger hole to go in and out of. I think I needed about 1/2" wood to fill the gap so I could use the old molding without having to get new stuff. I think I needed 1/2" by 2" tall by 36" long or 24" long. One of the ladders needed a spacer; the other one did not.
Tools needed:
You'll need a drill and lag driver; I have a impact driver and drill (2). You could use a rachet set and drill.
A step stool or ladder is also needed.
A hacksaw or recip saw with metal cutting blade.
14 lag screws (1/4" by 3" long)
Deck screws or similar for temp hanging
Paint for touchup/finishing
Caulk
Thin plywood or wood for filler.
I see the job as a handy-man type job. I doubt there is a company that would install it for you. Could get a handy friend and some beer and you'll be good to go.
~egon