I had the same issue about 4 years ago.
Me and an employee doing about £350-£400 a day from one van.
Here is what I did:
1. One man per van, with a 650L tank.
2. Converted all six weekly to twelve weekly at 50% more for 12 weekly, while at the same time canvassing regularly. Can now get a new customer signed up DD for every 150mins of canvassing, but it took a while to get there.
3. Got all new customers to pay by DD
4. Converted all old customers to DD
5. Used Go Cardless Pro for the above
6. Focused on doing quality work, with regular checks on work quality and logged complaints, and how many recleans we needed to do.
7. Timed all work, and dropped / gave price rises to all unprofitable work.
Now we are doing around £350 to £400 per day, each van.
With the team, they should be on minimum wage, and get 30% of the takings. They should get 'strikes' for stuff you don't want to see, like calling in sick. or leaving the yard late. The 'strikes' come off the bonus.
Explain to them that they can't come back before 5 unless the sheet is completed.
They get a further bonus for meeting monthly targets.
Yes, it is gonna rock the boat, Yes, they may / may not like it, but you need to get them onside and see the bigger rewards as being a part of it. Hire slowly, fire quickly.
The path ahead is not easy, and it takes time. However, if you've got this far, you WILL be able to take it to the next level.
Good luck, where are you based?