Two things to consider, first getting out is way more important than getting in, and second, you will probably be getting in without assistance (belay) from below. There are plenty of suppliers (Rock-n-Rescue, Rescue Technology) that have pre-made bail-out systems. Here is one http://www.rescueresponse.com/ on their main page. Needs to be coupled with an instructor belt (minimum) or (much preferably) a harness. Hook it to an anchor, and down you go. Pre-set to just hook into. It uses a high strength line (much smaller than what you would expect), figure 8 descender, and a couple of locking carabiners all in its own storage pouch. Are there better setups, sure, but it takes training to thread a rappel rack correctly (and if you don't check it, you just used your only chance), good static line for vertical rope work will not absorb any energy in a fall and will injure/kill you, and other descent devices are "complex" in relation. You can teach almost anyone to descend with a figure 8. By the way, forget what the military taught about bounding down the side. Stay in control and walk down backwards.

As for scaling the building, unless I have grapples, placement poles, cable ladders, or someone I know I can trust to belay me, I am free climbing it. Equipment is there to protect you in a fall, not assist the climb. Aid climbing equipment is very specialized and really not applicable here.

Best advice, find a local climbing gym and an instructor to teach the rest of the family how to rappel properly, then set up a pair of escape line packs with appropriate anchors at least thought out. Don't forget the chafing protection as well.

Regards,
Bill