Free car engine diagnosis?

August 20. Day 51.

Today's two askings:

I. I saw a coupon online for a free diagnosis of a "check engine" light. I don't have such a light, but my car has been mysteriously stalling recently. I called to ask if they'd look at it for free, even though it was a more complicated procedure. I added I would be open to fixing it there afterwards, or coming in for future services. The manager agreed, and was nice enough to keep my car all afternoon, run a few tests, drive it around (evidenced by the slightly higher odometer reading and lower gas gauge when I picked it up). The result? They couldn't find anything! The car was perfectly well behaved. I just hope it doesn't stall again tomorrow, when I'm driving my grandma to the doctor.

Gained I: Free exploratory diagnosis, valued around $80 at the other mechanic shops I had asked before finding this coupon.

II. Borders was the only bookstore I found in San Diego with theory books by Walter Benjamin, which I need for the chapter I'm working on. With two of his classics in hand (Illuminations and the second volume of his collected works), I asked the cashier if I could get the online price, which was $2 cheaper. She apologized, but offered this instead: a 20% discount if I was a Border's Rewards member. I happened to be a member, but didn't think to ask for that type of discount -- merely the online price. But asking for the first discount led to the second.

Gained II: $5.