When moving to Chicago, I checked with the Apartment Finders as I liked some of the places they had posted on Craigslist. they were the last company that I went with, it was just a fluke of scheduling.
They are the only place I visited that offered an array of free (non-alcoholic) drinks to their clients. Caffeinated soda was a wonderful thing to have when looking for an apartment.
The agent we met with was really nice, listed to what we wanted, and tried hard to find apartments that fit our needs. Unlike the other places, he actually had notes from himself and other agents on the places he was going to show us! Wonderful! This means he could actually answer our questions and avoid showing us places we were sure to turn down! This saved an awful lot of time.
We liked the one placed he showed us, but alas, we submitted an application the day before for another apartment (we wanted to keep looking in case we were rejected). While we checked out the place, he took his own photographs to help future clients.
Based on my experience, I'd recommend going with them early in your search. Just make sure that you know what you want and that you're upfront about it.
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