While there is always the risk of losing one of your clients to a competitor....you can mitigate that by...keeping your clients happy! Most of my primary clients...I've had for over 20 ...25 years.
The group of other techs in my state that I often communicate with, sometimes every day. None of them are right local to me, however two of 'em are sorta close....and have some of their clients in my footprint. And I have some of mine in their footprint. They're older guys like me, have their established customers that they've had for a long time.
One of them even called me to warn me once...of a customer they had, that they didn't like, customer was a reeeeeal pain, verrrrrry cheap, and they had a mutual departing. He told me "If such and such calls you, honestly...you don't want them". I already knew of this customer, from an onsite I did like...15 years ago, and I regretted that onsite, the customer had brutally cheap equipment and didn't want to spend the money to put decent equipment in. So, yeah the client called me later...saying they needed a new IT person, and I came up with some excuse, because...their IT guy warned me, and...I remembered them from 15+ years ago as being cheap. So I came up with some excuse like I wasn't taking on new clients, was trying to close up and retire.
Anyways, for 1x man shows, another possible benefit of getting to know other IT peeps in your area....work up an agreement about coverage. If one of you is sick, or goes on vacation, or you can join forces to take on BIG upgrades/projects.....help each other, and still make money together. I've helped some of the peeps in the group of 4 that I regularly chat with...be it phone calls...assisting on the phone, or even doing remote help with them.....one of the projects, for over an hour. He offered to pay, said "send me an invoice"...but I've received sooo much help way back in my early days over 20 years ago, I like to return the karma.
One of the 4 techs I've met a few times, he also owns a boat and stay on his boat much of the summer, and one trip I made with my wife....we took our boat back to my home town where I grew up and stayed at a marina he also has his boat, and we enjoyed many drinks together that weekend. Had a great time, our wives got along great, and I look forward to more "hang time" with them this summer.
Recently I created a Teams "Team"...invited them, and we're sharing notes and other stuff regarding NIST 800-171/DFARS/CMMC compliance. This relationship may come in handy down the line not too far, as....once CMMC comes into play, you cannot audit your own clients. So, we'll cross help each other here.