smurph, but no one is asking you to be a $200 ass. Bear in mind, that $200 service charge also includes a new o-ring or gasket seal (worth maybe fifty cents to a dollar retail?) plus an electrical test (and if it isn't a live test in a casket or a faraday room, that's worthless, but a live test could be worth $50?)...
So you're not just paying for batteries, you're getting a gasket and an hour of questionably skilled labor.
I'll be that makes it feel much better, like paying an auto dealership for a $99 oil change that "includes a 24-point checkup!" huh? (G)
ACR would have rejected my EPIRB because one of the internal mounting posts in the plastic casting was spalling out from the brass threaded insert in it. Why was it spalling out? Uh, because when they made it, they goofed?
A little epoxy made me happy enough. And a lighter hand torqueing the case shut. Oh, yeah, I also greased the gasket with silicone grease, since I have no idea where to get a new one to match.
As I explained to the nice man, "You don't understand. I would rather pack my own parachute, I don't know your man from Adam."
In late 1964, at Ft. Benning, Georgia, I went through jump school including learning to "pack" my own chute. I did so under the supervision of a Master Parachute Rigger that, then, had over 30 years of experience including packing chutes and jumping with the 101st at Normandy. More than once he pointed out my errors in sorting out and folding the risers. The first time I thought he was a PITA. Later, dropping out of the belly of a C-130 on a static line at 3,000 feet, I was VERY grateful for his supervision. Some times, with some equipment, a "minor error" can have very major, life changing, consequences.
If you don't share that opinion, do as you will--again, "Different Ships, Different Long Splices". Why engage in (poorly concealed) ridicule of others, perhaps more experienced, with differing opinions that, after all, have no adverse impact on you at all? In real life, two hundred bucks, or for that matter, two thousand bucks, is "chump change" when you're standing rectum deep in water in your cockpit, punching the "Here We Are, Come Get Us PLEASE" button, and you wife/child/friends are relying on you and your "Shoot Yeah, I "packed" it ma'self" may not get you all that far.
Sometimes, there's merit to relying on knowledgeable professionals when one's life may depend upon it. As to what you all do one your own ships? Frankly, Charlotte, I don't give a damn.