That is a super sweet birthday gift!
I sailed out of Chicago Sailing in Belmont harbor for 10 years before relocating to northern Michigan. In addition to renting, CS offers a timeshare type of deal that may be worth considering. There are 2 other companies that do this as well, one is Pinnacle, and I can't recall the other. Pinnacle has nice boats, but I've heard scheduling is tough.
We have taken some lessons from Chicago Sailing in the past few years and we have also rented the Hunter 326s from them. Part of the allure for owning our own is that we are not at all impressed with the way CS maintains their boats. In our opinion, they do the minimum possible to still be able to send their boats out on the water.
We've looked into the timeshare aspect as well, and with our work schedules we have trouble scheduling anything more than a day or two ahead of time, even though we do end up having most evenings free.
I by all means welcome alternative ideas, even if it sounds like I'm just shooting them down!