I have long thought there must be some way of making our children pay us back for the hours and money spent on them, the sacrifices our bodies make, and the nights (two years of them in my case) of their refusing to sleep through the night.

I mean, I know there's the love and all that stuff, but really sometimes it would be great to get some recognition in cold, hard cash.

There are ways of getting your revenge on them when they are small - for instance, dressing them in ridiculous clothes and taking pictures of them that will inevitably end up on stag or hen night T shirts and the like.

When my child, now 6, was younger, I simply clothed him in garments that made me laugh. Pink dungarees, little Chinese Manchu suits, hats with strange ears sticking out of them and huge gorilla faces.

And thanks to him, we got our first hutong home. Opening the door to a cherub-faced babe in a chest sling, how could the elderly couple living there refuse us board and lodging?

I'm not entirely sure they were intending to vacate so quickly, but I am convinced they gave the apartment to us because of him.

One of the most useful functions of children is being able to blame them for things. They're extremely useful for making excuses if you can't be bothered to go out, or are late for work, or any random reason at all really. It's what they're there for.

But I had begun to worry that as mine got older and lost some of his cute value, some of the benefits were dwindling.

For instance, seats on the subway or bus are pretty much guaranteed if you have a child aged 4 and younger, but at 6, the offers are getting sparse.

So, just as I was mulling over the loss of these advantages, my little charge came into his own in two ways. The fruit of my loins has actually started to bear - well, fruit.

We moved to a second hutong apartment when he was still little for 1,500 yuan ($236) a month less than my landlady - who, like all Chinese people, loves children - had advertised. I am sure this was thanks to my son.

When it's rent day, she only comes if she knows he's going to be in - and I always make sure I have dressed him in his most ragged clothes, best if they're a little small, and clutch him to me, bemoaning the cost of schooling and healthcare.

She hasn't increased rent in three years.

And then last weekend my little charge came into his own, in a way I'd never expected.

At Yabao Lu, we were looking for some school shoes. My son picked a pair he liked, and I proudly agreed 70 yuan, which is normally what I have to pay, even using the usual tactics of walking away and so on.

"No, Mom, they're too expensive," piped up my pint-size banker, who turned on his heels to walk away.

I explained to the vendor what he'd just said, shrugged my shoulders and followed him.

"OK, OK, come back!" the seller said. And we scored a 25-yuan reduction.

We moved on to Spiderman gloves, a Ben 10 cardigan, even a clutch bag for me.

And finally at a toy stall where, using the same tactics and helped by the fact that the stallholder also had a child, we got a remote-control car for just 30 yuan. They had started at 160 yuan.

There are 10 years or so before I can legally send him out to work, so there is plenty of time to perfect these new skills.

And it's refreshing to know that although we are no longer allowed to send our little treasures up chimneys, instead we can just pack them off to Silk Market.