I’m surprised at the level of the justification for what is, at best, poor communication and at worst a trainer taking advantage of someone new. No, a $25 fly mask is not unreasonable but why does the 4-month lease get stuck with that, along with all sorts of other charges he didn’t know about? Why is he paying the total bill for annual or semi-annual treatments? Most importantly, why weren’t these things disclosed at the beginning?
It doesn’t matter whether or not the charges are reasonable in and of themselves (although I would not be at a barn that still uses periodic deworming instead of fecal checks and appropriate deworming). What matters is that he didn’t agree to the monthly extra charges, he should have been told about and agreed to the routine maintenance charges, and he shouldn’t be asked to foot the entire bill for those maintenance charges, since this is a short-term lease.
What this sounds like to me is a trainer getting their bills for this older horse paid for all at once by the newby. The saddle is just a big pile of salt in the wound.
You can justify all of those costs (minus the saddle, which is someone advising their client to buy a very expensive custom saddle that “will fit everything” that in reality may or may not work, for their own profit), but you cannot justify not getting all of it in writing and explaining each one to the client beforehand. This gives them a chance to say yes or no, which I (cynically) suspect is why the trainer didn’t bring any of it up at the outset.
Yes, horses are expensive, and yes, older horses need and deserve maintenance, but no, people shouldn’t be taken advantage of so the trainer can get some of those expenses off their own bill or pad their pocket with saddle kickbacks. It’s gross and I am taken aback by how many people think it’s simply about costs and not about the lack of transparency and honesty.