For Sale Ads now Close 30 days after last posting.

While I understand why threads are now being closed after 30 days, I don't agree with it. Here's why - I have a car for sale. I am still getting replies from people interested in it, but it is "Sale Pending". I wanted to go back to the ad and add a post that states it is "Sale Pending", but I can't because the thread is locked. I don't want to mark it "Sold" until it is actually sold, because as we all know, sometimes these deals fall through. But it is kind of unfair for somebody to see the ad, get all fired up about it, only to find out the car is not available anymore. Seems like there is a better way...