Based on a true story.... Bought a ‘96 Tracker off craigslist back in June and I’m now on my second 12 oz can of brake fluid, topping off the reservoir every 4 days or so. Just small drops on my garage floor, under the front driver side caliper, so most leakage must happen under pressure while driving. Ill have to look closer at it all this weekend. It’s probably a reasonable expectation that I’ll have to get some refurbed calipers all around just to be sure.
UPDATE: Jacked it up and looked at it earlier today, and had one of my kids press the brake pedal while I looked at the caliper and line. The rubber portion of the brake line had a pinhole leak and was spraying a little jet of brake fluid out when under pressure.
I got a new brake line from a local store (called them at 9:30 am to request it, and they had a part for a 22 year old car ready in the store by 12:30. What an age we live in.) and installed it in about a half hour. Why was I so lazy for so long with something that could have turned into a major hazard?