Most 1031 Exchange experts will recommend holding your replacement property for 12-24 months to prove your intent.

Not following this would give a housing court judge grounds to award the tenant treble (triple) damages.I'm not an expert on every state but what you're saying doesn't make sense.

 You should review your state's rental property laws or consult an attorney.Usually the state requires a certified letter of lease non-renewal to be sent to the tenant's residence 30, 60 or 90 days prior to the ending of their lease. 

Certified mail of course!

Local experts who have done a few or more than a few deals and are looking to build their portfolio.

Hi people:)Would appreciate your advise on the following deal: 4plex, current rent 700 can be raised to 750/800. After remodel can be raised to max 900. No HOA, tax ~3k. Remodel cost 40-60k. How much would you pay for...

He is one of the many experts here on BP that are extremely knowledgeable in this area.  

(Please consult with a tax expert)2. 

I'm not looking forward to sending a bill via certified mail to ALL four of these tenants (they are all on the lease and all signed) but I'm guessing that I MUST?

Its all about risk management, until you become the expert in your area rely on those who are, you will find as you move forward most folks who are truly successful in their given field are more than willing to share that expertise and give some guidance to you.