Is there any restriction in using the FHA loan to purchase a duplex that I would live in when I already have a conventional mortgage on another property that is not my primary residence anymore? 

Figure your cost on a 1031 for relinquish (selling) is around $500-750 and on the replacement (purchase) is maybe $250 or so and a lot of paperwork, timelines and restrictions, if it is 10k and you have held it more than a year so it is long-term capital gains instead of short-term capital gains, then it is maybe saving a few hundred bucks...not worth it. 

Posting on Airbnb works too but restrict to only > 30 day rentals. 

I charge 100 per dog (weight limit and breed restrictions) and 25 a month per animal.  

There are some restrictions to this, including that the bank issuing needs to be 1st position on both loans.  

@Stanley Bronstein Yep, I ran into that HOA restriction already with some condos in Glendale; on the house the listing agent says he'll double check for me. 

For example, I've had clients want to buy a property zoned R2 but when I've looked into it, there isn't enough room on the lot to put a second residential property due to lot coverage restrictions and set back requirements, yet the seller was saying there was potential to have two units on the property. 

I've never heard of the court imposing a restriction on how much you can pay a lawyer to represent your case.

If you live in the unit you are tryin to rehab, you might be restricted on available funding.

I informed her that I had no language in my lease restricting my services or business for my space and needed to only be sure I was in standards of arizona law for my space.