If you want to manage properties that you don't own, then you'd need a license.You'd benefit from connecting with other landlords in the area that you do business in so that you learn the local regulations and requirements. 

Keep in mind that rarely, and I mean rarely do rental housing regulations ever come down to the size of the owner's portfolio.  99% of regulations will correspond to the number of units in that property not the total number owned by the investor.

Is this standard operating procedure?

I'm not advocating for never following rules you don't agree with... but the current regulations on STR's in GR are... well I'd estimate less than 15% of the airbnb listings are in compliance - (has to live there, can only rent 1 room, can't be away while renting, etc) - I'll jut leave it at that!

Due to stricter regulations in many newer condominium communities and it is less likely that your condo will become an illegal grow operation, drug manufacturing facility or party house4).

Don't want to deal w/ LA regulation when profit from Airbnb is starting to seem not worth it compared to longer term rental.

This procedure will help clean up any 'blurry' property lines you have in the future and will make it much easier for you to sell in the future. 

Additionally, even if it is not explicitly discussed/mentioned in your lease, you may run into some trouble with depending upon the type of property and any HOA rules + regulations.

They are SEC regulated. 

If you are going to bid on foreclosures you should know your state's laws and procedures.