> Unfortunately I have seen companies who are paywalling or purchase-walling manual downloads.
This is itself an enormous red flag of its own. I would never buy any product from a company that has its manuals online but then makes it difficult to actually download them. That's a worse sign than the manuals just not being up at all.
Bosch are nasty in many ways though. Their ebike battery and motor system in particular is extremely hostile to diy anything. Repair, generic battery with Bosch motor, using your Bosch ebike battery outside the ebike, ...
This is itself an enormous red flag of its own. I would never buy any product from a company that has its manuals online but then makes it difficult to actually download them. That's a worse sign than the manuals just not being up at all.