Note this is part of the "What's wrong with 1622 4th St NW series", but then I realized this applied to many houses being sold around here.
There are so many parts to a house and the conventional wisdom tells you only a few things that touch upon them, which may give you a sense of false confidence, for something in DC that puts you on the hook for a quarter or half a million dollars. You've thought you've done your research, but it only goes so far. This post, I'll just touch upon your home inspection.
I still have my home inspection from when I bought my home. My inspector did a decent job. He would have done a better job it he had a ladder and got on the roof. If we'd gotten on the roof, I would have been aware of somethings, that in the larger scope of things were minor and correctable in themselves, but those little things add up.
Also your inspector, unless he or she is Super Inspector with x-ray vision, cannot see through walls. And that's why I feel it is necessary to give a heads up to the person who buys this property to live in, or rent out. At 1622 4th St NW the framing style, hidden behind the walls, is unconventional, nobody is going to pick up on that unless the seller bothers to tell you. There isn't a lot of insulation and there is something about the firewall (you will have to email me about that because I'm not going to publish it here), but then again, these houses were originally built before building codes and pink insulation. Don't assume good stuff is behind the walls. Fixing stuff behind the walls in an old house is very unsexy and costly. Unless it is blown in insulation, insulating your home is not riviting dinner party conversation. It's just easier to turn up the heat or air and complain about utility bills.
There are great home inspectors out there. I've heard of inspectors who had discovered termite eaten beams hidden behind brand new drywall. Ones with ladders who climb on to a roof and look closely and can warn you that you may need to deal with X in a few years.