The biggest indicator that they should not be comped against each other is from the market price of each.  

The biggest downsides are that they usually have higher rates and require larger down payments.

Biggest thing here is they wants a house big enough for 2 separate living areas and house cannot have more than just a few steps to entrance and hopefully rear entry/etc.

The biggest thing you can do is build your CORE 4 which consists of getting a great realtor, contractor, property manger, and attorney wherever you choose to start investing.Let me know how I can help you get going

Identify the biggest losses and cut those with as minimal a loss as you can.

Biggest mistake I see is going to vacation and then half of the 45 day ID period days are gone or an investor looking for a (deal of the century and not being realistic).

Your biggest variable is going to be prop tax, and it changes from street to street. 

That said the biggest issue with heat provided is not the thermostat but the open window in spring and fall when the heat is on.

The biggest impact to your credit is payment history.Next biggest impact is your credit card utilization. 

I think the biggest benefit of it though is having access to the LOC.