As @Tom Gimer and @Peter Walther write, why wouldn't they isure is a vital question. 

If you are the LL, either an attorney can write one up pretty quickly if it's a complicated lease with special provisions, or your State Association of REALTORS should have a promulgated form you can use (I've had people pay me $150 to write on up for them in Texas where I'm licensed). 

Avoid the capital gains and use your Shedule E, LLC or business returns to offset passive income with great tax deductions and write offs.A fix and Flip can offer a good way to get some fast cash and deal with taxes in aother manner but again its still not the long game I think works best. 

But when you run the income numbers including  the other write offs 4 will outperform 1 every time.A 3% gain on 1 - $100k house is $3,000/ year.  

Write an insurance contingency into the offer. 

Tell them they still need to give 30 (or 60) days' notice-whatever the norm is there in writing.

Proper, Foremost and CBIZ are 3 that write them.

These are all things you need to do some homework on and figure out.In terms of BRR and flipping.Flipping makes you more money now.But BRR gives you the opportunity to invest, recoup your investment, have heavy depreciation tax write offs & build a portfolio which PAYS YOU IN YOUR SLEEP.You only have so much time to work, but the need for housing will consistently increase as our population is outpacing or supply of housing year after year.

@Jami Kloet, thank you so much for taking time to write about your experiences and your next adventures.

I never plan on selling them.They generate tax free income because these are in a ROTH, the taxes I would have paid in this income vs the tax write offs are severely in my favor.I can pull monthly tax free money out of this account, never run out of money as I can pull thousands of dollars in just incoming rent out.