I mean, local to me there are 3 or 4 fluid trainers for $75 or less used on Craigslist. That's how I got mine years ago. Sometimes instead of deal with selling on Craigslist local bike groups someone may give one away they are tired of sitting in a closet.

They're a dime a dozen and mostly bomb proof, until it isn't. Then it's largely disposable and not worth your time IMO.

If you're digging into replacing fluid or bearings, you could go rake leaves for a few hours of your time instead for $10/hr and make up the money difference to buy a "known good" one off someone on Craigslist. Just saying that to mean that your time is worth something also.