Often rules change eg tax laws etc  and these can have a significant impact on your dollar return.   Investors in particular may be interested in hearing about the  rules around Bright Line Tests.  How long you have a property for can affect the dollar return and you may want to consider  what you want to do ie hold long term or be happy to tick and flick and pay the tax and move on to the next project.  
You also need to know that you can't have two homes to call home even if you live in both 50%.  Make sure you have the information to make informed decisions about your real estate purchase and consideration needs to be given to the Bright Line Test.  
I talk to Tony Thorne, expert property accountant about this. At the time of publication of course anything can change and as always you must do your own thorough due diligence about your own situation.