Immediate goal is to buy our first income property, ideally a 4 plex.

Hi Elliot,To really analyze the deal, you'll want to factor in a few things (i.e. repair expenses, vacancy, etc) that you may have overlooked from your numbers above.Try searching for "50% rule" on here, or check out this (rather long) sticky thread to get an idea of things you'll want to consider:http://www.biggerpockets.com/forums/52/topics/17612-where-does-the-5-rule-come-from-

Ideally it would, if that's how the end buyer wants the property delivered (i.e. vacant).

Ideally, the tenants will pay you enough rent so that you'll live free, or close to it.

Chicago went up 1% in July & 0.5% in August.It looks like BP was incorrect on the appreciation factor.

Even though the problem is now solved, just wanted to point out one other possible factor.

Ideally web based, but would settle for a desktop application.

Ideally you would have greater success if all the properties were being handled by the same agent or at least by the same bank.

I may pull the trigger tomorrow.There are a few factors you may be overlooking. 

This is a pretty personal issue that depends on a host of factors including your current financial goals, investment opportunities, risk tolerance, time horizon, cash flow, cash reserves, etc.