Renting a Permitted Rumpus Room

[Austin N.]

Hello BP! I am currently analyzing a "duplex" in Los Angeles County that has a main house, free standing second unit, and free standing rumpus room (with bath). From my research and discussions with the city, all of it is permitted. The current owners are living in the front house (which they blocked off a door and are renting a big room as a "studio" with separate entrance), renting the second unit, and renting out the rumpus room. In total, 4 rentable areas.

Is it legal to rent out a legally permitted rumpus room?

If so, if the tenant stops paying and I need to evict, will there be any issues getting occupancy/back rent?

For the front house, is it legal to cover a door (with cabinets) and rent out a portion of the house? Appears to be the same as "renting by the room"

Thanks!