The 1973 version was one of the first things I bought when moving from a NY City apartment, where maintenance involved calling the super, to a 220 year old house previously owned by a succession of people who did it themselves and thought they knew what they were doing. Every time a tradesman walked into our basement, his eyes would light up, and a sly smile would flash over his otherwise imperturbable countenance. I had no skills whatever at that point.
We had no money at all to hire these guys. So within a couple of years, I'd replaced the entire hot water circulating baseboards, most of the supply plumbing, a whole lot of knob-and-tube wiring, added GFCIs, put in new cartridge circulators north of the boiler, and replaced the hot water heater. Among other things: windows, doors, toilets, on and on. Like the morning on the day we were leaving for Kazakstan, and I went into the basement to find a new pinhole leak that I fixed within the hour so we could make our plane without shutting off the water to the whole house.
This book saved me, conservatively, $15-20,000, and an enormous amount of aggravation. And the house became mine in a way it wouldn't have had someone else done all the work. The revision makes it better. Just buy the damned thing. Even if all it does for you is let you talk intelligently with a contractor, it's more than worth it.