If you were wondering if this place has changed, I can tell you that they have not.
I live about five minutes from their address and was looking forward to getting a mobile detailing company I could use long term to keep my two cars clean. So I grabbed two Groupons to try out the company.
As described in the other Yelp, you cannot get anyone on the phone. I called multiple times and left multiple messages. I received a callback one time, off hours, over a week after I left a message. Sadly I missed the phone call and never heard back from them again.
Groupon gave me their email address, or an email address that no one checks or responds to. Despite my later multiple phone calls, messages and emails, no one ever got back to me.
Top of the Line appears to use Groupon because they could not otherwise stay in business, as they are unable to schedule out the one and only thing they do.
Buy the Groupon at your own risk. I have just finally received my refund. What a waste of time.