I can't get to the list of all the properties from here, of course, but the company through various aliases does own certain buildings in the two regions, which they either rent out or use for company purposes. For instance, many of the buildings situated directly above the Goldenrod headquarters unknowingly have the company as their landlord. I believe it's the same with the Celadon headquarters?

[Because other people owning them would increase the likelihood of someone trying to dig out a new sub-basement and finding the Rocket base instead, naturally.]

When you put in the requisition paperwork for the key machine, ask about any unused storefronts in company properties.

As for Pokemon masseuses... that's a good question, actually. I'd think that Mr Mimes would have an advantage, given the flexibility of their... hands, but you could really make the case for any number of Pokemon with paws or hands as masseuses. That might be something to ask the otherworlder network at large? Having a few different pokemon doing different kinds of massage might be a draw.

Actually, it might be good to ask them for suggestions for things pokemon can do in general at a pop-up spa. We want to really sell the idea that this is a perfectly up-front enterprise, so we really can't half-ass that part.