My 20-year-old son and I followed our GPS into a gritty, deserted part of Chicopee, Mass. The apartment building for which we were looking was across the street from a funeral parlor and a few doors down from a liquor store. Trash was strewn on the sidewalk; the door to the building was locked.

We double-checked the address from the Craigslist ad. Then we got a text telling us to meet in a nearby alley. A man with a heavy Spanish accent nodded at us, pointed at a 2007 Toyota Yaris, and said, "Twenty two hundred dollars. Here’s the title. It’s signed over.”

“But that’s not your name on the title?” I said. (It was a woman’s name.)

“No. I buy and sell cars.”

There were no plates on the vehicle, which was not registered.

“Where did you get the car?”

“I buy and sell cars.”

“Can you tell us anything about its history, where it came from?”

“I buy and sell cars.”

All of my internal warning flags were hoisted, but my son, excited about his first adult purchase, said, “It’s fine, mom.” Then to the man, “Sorry” – with a look that said, “you know mothers ...”

The only reason I was even allowed to be part of this rite of passage is that he wanted a stick-shift and didn’t yet know how to drive one.

“You can drive down the street and back,” the man said. “Don’t let the police see you.”

The car was clean on the inside, shiny on the outside. We drove it for three minutes, which is what it took to go up and down the street twice.

“Feels nice,” my son said hopefully.

When we got out, the man was glancing around nervously — and then looked at us, waiting. My son started to say, “We’ll take —,” but I broke in. “We need to think about it.”

The man let us take a photo of the title. We realized later that his thumb obscured the name and address of the previous owner.

As the two of us drove away, I went over what I thought were some obvious red flags: We had no idea who this guy was. We couldn’t take it for a real test drive. Couldn’t take to a mechanic for an independent check. He only takes cash. We didn’t even know if he really owns the car.

“You’re paranoid, Mom. He showed us a signature on the title! And he seems honest.”

There was something beautiful about my son’s naivete, his youthful innocence and optimism. But it’s the kind of innocence that comes from never having been majorly burned. And if I could guarantee his life would continue on that no-burn trajectory, I would have supported that trust in his fellow man and joined in the optimism. Or at least bitten my tongue in the face of it.

Instead, I called up our trusted mechanic, who told my son: “Do NOT buy from an anonymous dealer on Craigslist. There could be major mechanical problems. I can’t tell you how many people come to me, having bought lemons that can’t be fixed. They’ve lost their entire purchase.”

But it was my son’s money, not mine. He spent all summer in the White Mountains of New Hampshire, maintaining trails for $9 an hour. He earned $2,000 for this car. It made my stomach sink to think of him losing all that. But it was his lesson to learn. And yet. It hurts to watch.

My son texted the man and offered $1,800 for the car. The man accepted much too quickly, and they arranged a time and place the next day to swap vehicle for life (albeit young life) savings. My son went to the bank and took out 18 cleanly pressed hundred-dollar bills in a white envelope.

For the next 24 hours, I tried desperately to come up with more arguments. “If you hand over cash, the guy will disappear — probably change his phone number — and you’ll have no recourse,” I tried.

I did talk him into asking for some sort of bill of sale, but when the man balked, my son got mad at me. “We’re scaring him off,” he said. To which I replied, “Don’t you think there’s a good reason for that?”

We called the insurance company; I was hoping they’d tell us they wouldn’t cover such a dubious purchase. Instead, the agent was a jocular type — and told us how when he was younger, he bought a car with cash, sight unseen, and could easily have lost all his money to a crook. It turned out okay, he laughed, but he would never ever do that again.

What I heard was, “never ever do that again.”

What my son heard was, “it turned out okay.”

The last thing I insisted on was getting the full name and address of the previous title owner. I was still worried it was a stolen car. Reluctantly the seller texted us the information.

Then I got to work. I managed to track the woman down on Facebook, then found her phone number in the White pages. When I called the number, her husband answered. Yes, he said, they did sign over the title. As my son mouthed "See?!”, I apologized for bothering them and was about to hang up. Then the man quickly added: “But you’re not planning to actually drive this car, are you?”

I put him on speaker.

He explained that the car was completely rotted underneath. The back wheels were about to fall off. It won’t pass inspection. They sold it for scrap on Craigslist a few weeks earlier, and they were shocked the guys who bought it drove it onto the highway. They had warned that it was not even safe to drive down the block.

At that point, I looked at my son’s ashen face. He finally got it; he would not be buying this car. I was engulfed by relief.

My son texted the seller and lied that we found another car. And we spent the rest of the night watching mindless TV and feeling emotionally sideswiped, having managed, just barely, to stave off a used-car disaster.

The perfect lesson, right? No money lost. And Mom was totally right.

The thing was, a part of me didn’t actually want to be right. My son was chastened, for sure, but he was also somewhat beaten down. I wanted him to have a good result on his first major grown-up transaction. I wanted him to enter adulthood with optimism and trust. Instead, he felt betrayed, embarrassed, and deeply disappointed in his fellow man.

But at least, I told myself, he won’t put himself in such a vulnerable position again.

The next day, my son sat down again at the computer. He logged onto Craigslist and saw a Toyota Corolla for $1,850. Looked nice.

"But you won’t buy a car without a mechanic taking a look, right?” I said.

“Right,” he said. “Well, unless they seem really honest.”

Karen Brown is a public radio reporter, freelance writer, and essayist who lives in Western Massachusetts.

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