One way to get clients to respect your input is to charge a lot.
Many contract shops would be happy to tell you that "no one will pay that", pay you $65 hour and then turn around and charge $130+.
or $55/$150 in my case :(
I know some people can go 30 years and not have any friends they used to work with. At the very least, you should make contact on LinkedIn for your (former) colleagues when you leave a job. Drop them a line once in a while. “Ping” them a text at Christmas, etc. You don’t want to wait until you need work to start building your network.
Sorry, I didn't answer your question. Yes, to some extent, they just can't find someone else to do their project. I've got a kind of bizarre mix of skills I guess.
I'm not sure what you mean exactly by "highly-targeted". I don't look for clients, they just fall in my lap. They probably fall in my lap because I have those skills (and some others). The typical job goes something like this: someone I've worked with before asks me if I'm available and if I could do something like X. I tell them, "Why yes, I'm an expert in X, as far as you know." (Just kidding.)