Let's see if I can benefit from my kids' avarice

For a couple of weeks now, I've been at that point in pregnancy where it's almost impossible to get anything done, because I have to sit down and rest.  So cleaning the kitchen goes something like this:

• sweep, 10 minutes
• rest, 15 minutes
• wipe down counters and stove, 5 minutes (small kitchen)
• rest, 10 minutes
• mop, 10 minutes
• rest, 30 minutes

This doesn't account for stopping to run an inquisitive toddler out of the room, to the potty, etc.  So what should be maybe a half-hour's work winds up being a lot longer, and then I'm flattened for much of the rest of the day.  It's...inefficient.
Enter Capitalism, which I am told will make all our lives better.  The kids don't get a regular allowance right now.  (They do have chores, which I refuse to tie wholesale to allowance because the chores are things you do because you're part of the family.)  Like all kids, mine like to have their own money & the opportunity to earn it.
I don't have my camera handy to take a picture, but I just made up a sign that looks a lot like this:
Ways to Earn Money!$1 for:Sweeping and mopping

• kitchen
• dining room
• living room
• bathroom & hallway
• your bedroom

Scrubbing tub or toilet or kitchen sink
50¢ for:washing pots & pans (doing the regular dishes is part of their chores, but this Erik or I typically do)washing off dining room tablereading Marie or Esther a book/storypracticing "to, with, and by" reading with Estherpicking up trash around the can (like most kids, they throw stuff at it)
25¢ for:helping Esther do any dollar job without yelling at her
10¢ for: helping Esther do any 50¢ job without yelling at her
Always ask if there's a special job!
Of course, I'm going to be doing this stuff as much as I can anyway; one of my main goals here is to turn the kids into the help I will need when the baby comes.  There'll be at least a few days when I won't be able to do this stuff by myself, & I'm hoping I'll have greater cooperation if they know they can get paid to help out.
Maybe I should add a small daily payout for doing their chores without whining...