Hi John,
You should check with Lewis/Romeoville. KLOT. It is probably about 18 miles from Oakbrook Terrace but not in bravo airspace. They also have rental cars on site. You can check with the airport folks about the tie down. I know they have new astro-ports and hangers. Chris is the airport manager who could probably get the information. Here is their web site.
http://www.flylot.com/
There a few RV's on the field too. They have more services available than at Clow which is a little north of Lewis.
Hope this helps,
Paul