Having a vacant unit/vacant home allows you to freshen it up before sale, giving you a better ROI. 

If you have equity, consider pulling out money to invest with a home equity line of credit.Also, because you have a schedule that can allow you to actively work as a Realtor, I would encourage you to get your real estate license, as I did, and begin networking with other local investors and helping your sphere of influence buy, sell, and invest.

If you scroll back to @Brittany Minocchi's comments you'll see that I am apparently correct and they are allowed.

As applied to 1031 exchanges, the most relevant exceptions that allow you to disregard FIRPTA include:You (the Buyer) are going to be using the property as your principal residence, and the fair market value is less than $300,000The Seller provides you with a Certificate of Non-Foreign Status (meaning that FIRPTA does not apply)If the foreign Seller obtains a FIRPTA Withholding Certificate by filing Form 8288-B.It is important to note that the foreign Seller cannot submit the Form 8288-B until there is a valid real estate contract.

Shivani, these are hard money, short term bridge loans allowing you to improve the property for either sale or rental. 

Also, the town of Spu, TX and possibly a few other towns now straight up allow tiny houses in their town.  

Investors analyze income, costs, financing conditions, market rents, operating efficiency, and other dangers in order to assess cash flow potential.Increased revenue from tenants, extra sources such as laundry facilities, parking fees, and storage rents, as well as mortgage payments, property taxes, insurance, maintenance expenses, utilities, property management fees, vacancy allowance, and capital expenditures.

This allows the Appraiser to perform the inspection as quickly as possible and avoid delays while working around your schedule.- Do your own neighborhood market research.

This would allow you to eventually plan strategically to move into the new house and convert your current primary into an investment property... to then 1031 into your next project(s). 

Creekshire Village also adopted this measure and now will only allow investors to have 1 rental property in the community.