Illiniwek Forest Preserve: Tour e Visite Guidate

I've been to Chicago many times so I knew the location and I always thought it was just perfect and I was just waiting for the right opportunity to stay there. When I got there my room wasn't ready yet but I was offered the option to upgrade to the vista suite for a very convenient price, which I accepted and very much appreciated. Only negative observation: at check out I was told I was all set but I wasn't emailed the invoice with the extra costs, which I also requested as the amount charged on my credit card was not the same I expected; it was probably correct but I wished to verify and I never got a reply, which is quite disappointing. For my next trip I will request to see the invoice when checking out.