With the greatest respect to everyone on here, turning over £400 a day could be achievable for some guys who have large rounds and operate more than 1 van with several other employees on minimum wages, but most of us operate alone without any additional labour!
I have employed guys in the past and always paid really well, (£12 per hour), starting at 8am and finished by 2pm, but everyone of those let me down or became greedy, so they were fired. They all thought whatever I turned over for the day was going into my back pocket without thinking I had to pay HMRC, the overheads of the van, equipment, servicing and insurances before even getting to wages.
Realistically, I aim to earn £200- £250 per day and thats working 8am - 2pm by myself.