In an effort to make this a vacation rental, I am building where I knew there were restrictions.

I also want to know more about zoning restrictions because I may see a Triplex for starting out and could possibly build a live able unit in the back of it.

Two other things to check are Deed Restrictions and the presence of the HOA and their CC&Rs.

The ordinance that is almost about to be put in place specifically allows it but under certain restrictions which I'll list below. 

Is their a law to restrict or punish this kind malicious litigation?

If you convert your home prior and decide to rent or live else where in the interim, then decide to use FHA to qualify for a new primary you can use the rental income with out restrictions of the 100 mile rule and still qualify for FHA.Their (FHA) guidelines are rigid, but with proper planning you can adhere to the guidelines and accomplish your objectives while avoiding the unintended consequences of the rules.Best practice would probably be to wait a few months after moving till utilizing your FHA loan to obtain another property.FHA does have a max of 7 financed properties including the FHA insured property (6 rentals + 1 FHA primary) so it looks like you're riding up to your max with the current of 6 financed properties.

--Noticed that many communities have HOA restrictions, mostly for road maintenance...but several restrict weekly rentals as well.  

Whenever there is any condo/townhouse listed for sale, I would like to read CC& R (Covenant, Conditions & Restrictions) and bylaws.

The only thing I can think of is some kind of restrictive covenant that may exist if the two lots used to be one.  

All for AIRBNB’s if anyone has information on local codes or restrictions.