If you bought it with the primary intent of reselling then your exchange will fail under audit.  1031 is used for property you intend to hold for productive use in trade business or for investment.  

There is - typically - no way to expense the entire amount in the year where it's bought, at least not for investors like us.As a rule it can be said that pretty much all the stuff one, as a landlord, would put in a rental unit is 5-year property.You really need to have a CPA take care of this or you'll run into trouble or at least make mistakes that, in a potential audit, will cause you trouble.

Can anyone recommend an online rental payment system and rental software?

I think you would have a hard time defending that should you be audited.

I have recently begin my real estate investing business and need some recommendations for computer software to track tenants, units and finances.

I get them from my software company Rentec Direct, but there's a few other options for directly ordering them too. 

Make sure there is a solid existing infrastructure for accounting, legal and audit.  

I worked in software/web development for over 30 years before calling it quits..

Have been in software sales over the past 6 years and currently building a foundation for pursuing real estate investing.

I don't see this as a guaranteed red flag, as in if you claim it for this year it could trigger an audit about why you didn't last year.