Darrell,I ran into a similar situation last year. 

First, all first flips take 2-3x as long as you think and cost 2-3x as much as you think.

how long will it take you to get your $40K back?

I understand that the Section 121 Exclusion for Primary Residence allows you to sell your Primary residence and not have to pay ANY capital gains taxes on the gains/proceeds - as long as you use those funds to purchase your next Primary residence.What I cannot seem to find the answer to is - what is the maximum timeline allowed from Sale of the first Primary to Purchase of the replacement Primary residence? 

However the previous owner will be in the military for a long time, he's on the note, and so the bank can't foreclose.

The property has an existing long-term tenant and is cash-flowing.

I am a long time listener and advocate of the BPP.

I'm assuming this is for a long-term rental property.

I am looking at establishing a new single-member LLC.

If you have just one long-term tenant in your house hack duplex, and you're taking a $30,000 guru course on making money from assisted living or storage facilities or on running a syndication - it is probably not deductible under Section 162.