there are some apps that you can use as well. one is called ez-inspector and I cannot recall the others but if you maybe do a search you will find some apps that you can use that will make your life easier, keep electronic, keep it on the cloud makes it simple easy to retrieve for any future need

I only have one sfr.Just installed:http://www.homedepot.com/p/Kwikset-SmartCode-909-Single-Cylinder-Satin-Nickel-Electronic-Deadbolt-Featuring-SmartKey-909-15-SMT-CP-SCR/205597290Another good option:http://www.homedepot.com/p/Kwikset-SmartCode-Satin-Nickel-Electronic-Tustin-Lever-Featuring-SmartKey-911TNL-TRL-15-SMT-CP/205597285

I was looking for an electronic lease or agreement app

I was planning on purchasing some additional homes to rent out as ST units in other parts of the city that are not necessarily by the Oceanfront.

See below from the IRS site: Responsible PartiesAll EIN applications (mail, fax, electronic) must disclose the name and Taxpayer Identification Number (SSN, ITIN, or EIN) of the true principal officer, general partner, grantor, owner or trustor.

No because not everyone can (or wants to) pay with cards or electronically.

Always use a PO Box or mailing box address for all documents like deeds, mortgages, real estate taxes, utility bills, tenant checks.Eighth, never accept cash from tenants, only checks, money orders or electronic or direct payments.Ninth, never tell anybody how many properties that you own; evade the question or give a nebulous answer like a couple, a few, only this one.Tenth, own every property in a different name, and not a serial name like, Nicolas property # 1, Nicolas property #2, etc that shows the relationship between properties. 

John did everything over the phone and electronically so I never even had to go to a branch.

I think it's free for 75 units or you pay $10 - $15 for an upgraded version that allows for online payments, electronic signatures, and some other features.Software is a common question on BiggerPockets.

I have no idea how much or what logistical challenges I would have in the way of furnishing, buying electronics, etc.