Lactate testing - I do my own testing. You can find people to test you but they usually run suboptimal protocols, charge too much to do it frequently, and often don’t know how to look at the data and just run a canned software analysis.
Broke down the costs in my MLSS thread here: Lactate Testing - Data and Results - #6 by DarthShivious
Short story is about $500 to get the meter and associated disposables to start-up. Once you cover the equipment expense, each future test works out to about $2 to $2.50 per data point. From there it depends on what protocol you run.
I charge buddies $20 per test. But that is a terrible business model (LOL)
-Mark