1st Duplex Under Contract - Need advice!

[David Collier Jr]

So after using my BP gained knowledge, analyzing and offering on too many properties to count I got a great deal under contract. Now to figure out the next steps.. Any and all advice is very much appreciated. Everything I learned on BP and put to practice is the reason I have this opportunity. 

I know it makes most financial sense to move into the property to keep my living costs down. Units are a 3/2 ($1,300) and 2/1 ($1,100). I prefer to move into the 3/2 (need the size) to keep my down payment requirement low to free up capital for another purchase . Also it needs slight updating to bring rents to market (+$300).

The tenant in the 2/1 is very ideal, working at sea and only home 10 days a month. I prefer to keep him in place as there is low wear and tear. His rent is also below market by about $300 w/ updating.

The current tenant in the 3/2 is long term (3+ yrs) and has expressed she wishes to stay. She seems like a good tenant with the exception of two pets and seems to have a friend living in the property who is not on the lease. Her lease is up August 31st. Closing is scheduled for mid June. 

My plan is to wait until after the closing to notify the tenant of non renewal. However, I just read the leases and it states she must notify landlord of renewal 90 days prior to the leases termination date. This means she will be submitting a renewal notice prior to my closing. 

Do I have to honor that renewal? 

Should I inform the listing agent (current property manager) of my intent prior to closing?  I don't want it to affect the deal. 

I also want to make the transition as easy as possible for her and provide as much notice as I can. I just don't know how long I am required to move into the property after closing if I state to my lender it will be my primary res (FHA or Conventional). Does the unit have to be vacant at time of closing?

Thank you again for any advice!