The chance of it being the missing link within a hospital seems large though. I imagine there are more beds then there are ventilators in any given hospital.

So the plan is to keep one around the house, maintained in good condition, to take with you to the hospital?

No. The current survival stats involve 20% of those infected ending up in ICU. If this was to become a pandemic that would require millions of respirators to maintain that survival rate. Think about that and what "condition" you would accept for a respirator.

And if the staff is t trained on that particular model, there is no way they’ll use it.