Make sure you and your contractor get the right permits but all you have to do is add temporarily walls to where you want to section off.

Never took the gray wall Kool-aid.

For instance, one property seems to have an extra bathroom that is not listed in the county records.I plan to make some modifications, including removing a closet wall to expand a bathroom and taking out a kitchen island that contains electrical outlets and a switch.

For example, you want to add a wall to create a bedroom.

Also, per the images, a crack develops in the kitchen, on the other side of the house where the wall meets the ceiling. 

And then you will purchase a new investment property and all of the gain is tax deferred indefinitely as @Jaron Walling said.The way to combine and get both advantages would be to move out and turn that property into an investment property for a year. 

& different parts of the asset can be depreciated on different schedules.To find out the useful lifespan of each component, you do a cost segregation study to analyze all of the parts.The raw land can't be depreciated so you start by giving that a value first.But other items can be depreciated on a quicker timeline.A roof, road, sidewalk, fencing, walls, gates, doors, latches, flooring, air conditioners, pavers, curbing, landscaping, etc.The IRS has a depreciation schedule for each type.Some parts are 5 yrs.

From what I've read in the Wall Street Journal, Austin's push to increase zoning for multifamily developments seems to be making a real difference.

Outside the walls of my home, in the general public, I can't think of a single instance in my half century on the planet where having a firearm would have changed a situation or where I found myself in a situation that I could not walk/run away from to avoid conflict altogether.

Quote from @Rose Jones: The #1 problem with fish tanks is that they leak and cause damage to the floor or walls.