What rent price range is best to own in strong rental rental area

[Mike Nelson]

My focus here is Wicker Park in Chicago, which is a strong, above average rental market.  The situation here may be similar to similar areas in Chicago.  The rents here range from $1200 to $2700 for a 900 square feet two bedroom apartment.  My units are toward the lower end.  I get quite a bit of response to my ads, and are easily rented.  I was wondering if units toward the middle or top of the price range are easier or more difficult to rent?  I suspect there is more demand vs. supply for the cheaper units vs the top end, but there are other considerations, such as quality of tenant and property values.  This question pertains to Chicago, but may apply to other areas as well.