Where i have seen owners get fubared is they have a renters policy and there is an exclusion for when the house goes vacant and they do not know that and then something happens to their rental and they get denied..

Yes, you'll owe tax on the gain. you're well outside the two years residency out of the last five for the 121 exclusion.

Just because you come to terms on price you do have to also do due diligence before you sign the contract and become exclusive.  

Your brother-in-law’s 10% ownership won’t affect your ability to claim this exclusion on your portion.Unfortunately, the option to roll proceeds into another property (like a 1031 exchange) only applies to investment properties, not personal residences.You’re likely eligible for the exclusion, but I recommend confirming with a Tennessee tax professional for any specific state tax issues and to verify your status with overseas residency.Let me know if you need more guidance on this or related financing!

From a sales perspective, if you're married ($500k) or if single ($250k), you'd have a portion of the exclusion (%50) assuming the square footage is the same for each unit (assuming a duplex)The remainder (%50) could be 1031 exchanged into another property tax deferred. 

For example we write exclusive use of the rental property includes use on two sides to the tree line, on one side to the rock wall and to the front curb. 

Capital gain can be avoided by using sec 121 home exclusion (upto certain limit).

Think about partnering with local event organizers and advertising your place as a perfect accommodation for visitors.Seasonal decor: Make your property feel cozy and festive during the holidays, or provide season-specific gear like beach chairs in summer or sleds in winter.Local Partnerships:Experiences and services: Partner with local tour guides, restaurants, or even spas to offer exclusive deals or curated experiences for your guests.

But, excel is totally fine in the beginning (in addition to your PM software to capture transactions outside of the properties).We use QuickBooks Online exclusively for all of our REI Clients.

The past five years here in Oregon I've focused almost exclusively on investor related acquisitions and sales of vacation rentals, multi family complexes and commercial real estate.