The Paris thing seems almost like buying a rent-controlled co-op apartment in NYC. Apartment for sale for $350,000. HOA + tax (combined payment) are say $800/mo. Tenant is paying say $415.31/mo.

Tenant has a right to occupy the place till death do them part, but their children could also move in and then THEY have the right to occupy the place for life.

So you might be stuck owning the place, paying the difference of the rent-controlled rent and maintenance for a VERY long time…