Wow, great stories! My dad once took a car engine apart just to look at it and see how it worked. I've installed engines and a heavy-duty transmission and assembled a lot of stuff, but I never really had the bug that bad. I'll fix things if I can, but I don't really enjoy it (well, unless you count rebuilding and refinishing that one bass guitar).
Locked out so soon. I feel for you. I live in dread of the day I lock myself out of my apartment. If it's a weekday the office has keys, but at night or a weekend? I'm glad your neighbors are turning out to be cool.
Bookshelves. Bookshelves are good. I'm glad you said why they are on their sides, because I was just about to make a snarky comment about how they are supposed to work.
Cold feet? Now you know why your sister has a husband. Trucks and handymen are nice, but a girl needs someone to warm her feet on. Someone to say "Don't do that! Yer feet are cold!"