With this scenario I think one of the biggest decision factors is, are you eligible for a sec 121 exclusion? 

What have your experiences been on this topic, and what factors do you take into account when making this decision?

I'm from a commercial background, so cap rates are my go-to, but I'm not sure if that is as much of a factor in smaller two to four unit multi family. 

It's based on very specific conditions, seller type, market, and other factors that are too involved for this format. 

A couple questions and thoughts that have came across my mind are below.Contributing factors: (My goal like most newer investors is to reach financial freedom)-Area: Western Suburbs of Chicago.

number, frequency, and substantiality of sales [this generally is the most important factor (Suburban Realty Company)]; See (c) below iv.

Then you need to factor in the cost to finance if you are doing so (ie. underwriting fees, closing fee, etc.), holding costs (utilities, property tax, etc.).

In my experience flippers make the quality of a city improve, but like @Greg H. said, there is the "you aren't from around here" factor at play.

If you purchased a property, significantly rehabbed the property and immediately sold it thereafter with the intent of flipping it, it will be subject to self-employment taxes.Regarding the taxes you will be subject toFederal TaxesState taxesDepending if it was a flip or not, also self-employment taxes.Speak with your accountant on the actual taxes that will be due as he/she will know what your marginal tax rates are.You can also factor in improvements / selling costs to decrease your gain / taxes.

I did more research and thinking after I posted and I determined that I am likely eligible for the primary residence exemption on taxes which negates the capital gains factor.