This fellow inspected our first home before we bought it. He was recommended by our real estate agent (first red flag) and we were in a bit of a rush, so we went with him.
He spent a couple of hours at the house and seemed to know what he was doing. However, any time I pointed out something that was obviously a flaw, he tended to downplay it and calm my fears. The agent was there for the inspection as well and she backed up everything he said. It was obviously in her interests to get me to buy the house and it was in his interests not to get in the way of that possibility. I can only assume that he picks up a fair amount of business through her recommendations to clients - if he gets in the way of deals, he'll probably get less business from her.
Specifics:
1) The basement was a home reno job, including electrical, and it has since become obvious to me that this wiring would not pass inspection and that no permit was ever pulled for it. This is obvious from sloppiness at the electrical panel and elsewhere where the wiring isn't covered. R. (inspector) did not detect this or did not put it in the report - either way, that would be enough for a bad review.
2) Damaged roof sheathing viewable from attic access. He pointed it out but said it was dry and wouldn't be a problem. Well, when it rains, the roof has been leaking in that spot ever since we moved in and, as luck would have it, straight through the bathroom fan into the main bathroom. Looking at an expensive repair this summer.
3) I pointed out that the garage was described in the listing as "insulated" and I couldn't see any evidence of insulation. I pointed this out to both of them during the inspection and was made to feel like I was nitpicking and that it wouldn't take much time, effort or money to insulate the garage.
4) He did not detect a sump pump in the house, even though the exit pipe is plainly visible on the exterior of the house and steel plate cover was in that vicinity in the basement. We moved in, not knowing there was a sump pump and, within a month had a flooded basement because it had failed.
5) He told me the pot lights in the kitchen would have to have vapor barrier hoods installed over them (in the attic) so that they didn't cause condensation and ceiling stains. After we moved in, I did some reading and saw the "IC" designation on the inside (viewable) side of the fixtures. R, if you're reading this, look it up - I'm not going to teach you about your trade after paying you my hard-earned money.
In fairness, he did detect some things - every home has flaws - but I certainly don't feel that I got my money's worth from the inspection. The items I have listed are "plain view" issues that would have impacted the amount we offered.
I will not be going back to this firm (or probably any home inspection firm) ever again. All they do is look at the surface of things and if you have a couple of hours and a checklist you can do all or most of it yourself.