The check-in girl at the car-hire place is just doing her job. "You know," she says, "we've got a special deal at the moment. For an extra $US35 a day you can upgrade to a convertible. What do you think?"
I think there are probably better things to spend your money on than an enormous, gas-guzzling sports car and that's what I'm about to say before my partner almost physically elbows me out of the way to get to the counter.
"We'll take it!" I raise my eyebrows. My partner grins. This doesn't seem like a very good investment, but it's already a deal.
"Great," the check-in girl smiles, tapping her keyboard.
"You've got a brand new Mustang convertible. It's only got two miles on the clock, too. Brand. New. You guys have fun, OK?"
OK. Except, I don't really drive much at home, so I'm not sure how this is going to go, especially as we're in California, where I'd been a little worried about having to drive on the other side of the road anyway. And now you're telling me I'm going to be doing this behind the wheel of a spanking new muscle car?
I am. There it is in the garage, too, looking all tough next to the boring family sedans and SUVs.
It's like a spaceship inside, with glowing blue lights and bucket seats (which would admittedly make it a pretty lame spaceship, but work with me here).
I turn the key and the Mustang growls then settles into a contented little rumble, huge pistons slowly pumping, begging to be allowed to do what it was built to do.
A Mustang. An American classic. Now that I think about it, this is doing things right. The founding fathers would have wanted things this way.
But it's still scary. Don't get me wrong, I'm happy to be driving this rumbling beast, I'm just petrified of crashing it. It's a sports car but it feels enormous from my sunken position in the front seat, like I'm piloting a ship while hiding out in the galley.
Our Mustang is quickly given a name. I know real car people don't name their cars, but we're not real car people.
He - yes, it's definitely a he - begins our journey being known as "the Mustang", but within a few minutes has morphed into "the 'Stang", then a while later becomes "Steve the 'Stang", until we eventually settle on "Steve Holt". That's in honour of the character on the sitcom Arrested Development, the high-school football star who, upon walking into a room, will always raise his arms in the air and yell out: "Steve Holt!"
Our car seems similarly subtle. I ease Steve Holt gingerly out of the parking garage and hit the highway heading into San Francisco, giving a few little taps on the accelerator to make sure that, yes, there really is a huge engine rumbling away just in front of me.
Slowly I get used to this hulking beast I'm in charge of, used to driving on the wrong side of the road, used to driving at all, and suddenly ... Wow, this is fun.
And we haven't even had the best of Steve Holt yet. The next day the sun is out in San Francisco, and there's only one thing the owner of a convertible should be doing on a day like this: getting that top down and hitting the road.
So that's what we do, pulling levers and pressing buttons until Steve is topless and we're ready to tackle San Francisco's finest streets. The rumble from the exhaust is even louder now and Steve's begging to be let loose, desperate to show the world what he can do. (It's amazing the emotions you can assign to a lump of metal.)
We hit the road, making our way through the hilly city before crossing the Golden Gate Bridge, staring up at that world-famous edifice from the open top of our beasty car.
Steve owns San Francisco, but he's not done yet.
He eats the freeway for breakfast as we tear up to the Napa Valley, before roaring around some bends as we swing back south for a slice of the coast-hugging Highway 1, a road that seems custom designed for a topless muscle car and a pair of giddy tourists.
And to think I hadn't wanted to do this. If I had my way we'd be pootling along here in a mid-size sedan, saving fuel and saving money. Playing it safe. But Steve Holt, the topless wonder, has changed my mind.
As we motor down Highway 1, the wind whistling, the sun shining, the birds possibly chirping but inaudible because of Steve, $US35 a day seems like a very good investment.