I manage on Oahu in Hawaii and I would assume based on things that I have heard from other hosts and managers in CA that the conversation around regulation would be somewhat similar given that it is a highly desirable destination for both guests and investors in the STR space.Speaking only to what I have experience with here - there seem to be three types of zones that vacation rentals fall into - on one hand you have zones where they are illegal, and while it is possible to run and gun in these areas I don't think the risk is worth the reward if you get caught.

Land Acquisition: Look for land in desirable locations with good growth potential.

They acquire things but don't put very much desire into keeping them when they move.

That resume will determine your future.Prime example, buy a few lower than desired cash flow properties now and into the next few years vs. investing in a good yielding stock/fund at 7-10%. 

It seems a great HVAC guy is really hard to find and worth his weight in gold in Florida. 

The market doesn't care what you desire for cash flow....it only yields the same cash flow that every other property will have. 

If the statements are true encourage as desired.  

Use keyless entry and can even have wifi locks if desired. 

Now, this doesn’t mean these are areas you should shy away from, it just means you must be willing to follow those rules that are set and make sure your proforma numbers reflect your desired ROI.

@Navid SadighiNowhere in your post did I read that your parents desired, or were in need of more income.Your father seems to have done a few things right in his lifetime.