We use money as a medium because barter simply doesn't always work. Imagine you try to barter your photography services to a photographer...not very valuable, eh?
But, when you think of your services, I'd encourage you to think of them in terms of dollars. What is an hour of your time as a photographer worth? Let's put a number on it - say $100/hour.
A lot of good info there. Please feel free to ask me about service. I am on Long Island so geographically you are far but I will answer any question. Lamp wise, led not really needed as the 75 watt usual is not that hot. I have seen many 23c 111 with no heat shield at all and no cooked negs. Alignment with a laser is fairly easy with practice. Or a parallel ...
Most of it is common sense. I am a maniac, so let me categorize things. Maintenance, in general, is divided into two categories.
The first part is to actually know the stuff. So take a screwdriver, on a clean desk and try to disassemble some ...
Here's what I'd do:
Take it apart and blow it out with dry compressed air
use specific bulb designed for enlarging if you change bulbs
clean the condensor (s) with lintless wipes and use lens cleaner
spray some wd-40 on a rag and wipe the gears and tracks with it, use very lightly and sparingly
If the elevation lock is broken fix/replace it... duhhh!