To the OP.
You mentioned that there weren't other lease horses at your current barn, but that doesn't necessarily mean you need to jump in to ownership. Perhaps you could lease from elsewhere (with the guidance of your trainer) and board the new horse at the current stable to continue under the current instructor.
(Unless I read that all wrong, of course!)
It's hard to change mounts sometimes, but if you're staying at the same barn, you'll still be seeing the pony, won't you?
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