We have basic, expected chores that are not tied to money (dishes, a meal cooked per week, bathroom cleaning, vacuuming, basic laundry etc) - they're all things that are just part of living together with other people, and it's our job as parents to make sure they know how to do them.
We give an allowance each week and have an expectation/rule that they will divide it into thirds - spending, saving, giving. If they want anything, it comes out of their spending. Saving is long-term stuff, really and we haven't made clear expectations as to what this is for - but it goes into their own bank accounts and they watch it earn a little interest.
On top of that, there is the occasional job that we offer payment for - like the girls share the lawnmowing from time to time and get paid $5 each (we have paid a neighbour boy $10 to mow the lawn in the past).
Or a couple of weeks ago I really needed an old fridge cleaned out before our new boarder moved in, and I just did not have it in me to do it myself (heavily pregnant, exhausted), so I introduced a 'tender' process. I told them what the job was, what my time-line was and that I'd give the job to the lowest bidder. They went away, thought about it and talked about it, and came back with their offers (delivered to me in private so no-one could under-cut). Mr5 said $30, Miss7 said $14.80, and Miss10 said $12. So the job was Miss10's. She tends to have a bit of a problem maintaining focus, so I said that she had until 4pm the following day, and that I'd be penalizing her $0.50 per half hour that it took her beyond then. She did a great job, and finished right on time :-)
In hind-sight, next time I'll need to remember to state that if all the bids are too high, then the job will pass in, and I'll do it myself. Miss7 is a very strategic thinker, and I can see her organising a conspiracy to over-bid, in return for profit-sharing.