I would take a long time and agree with your point, it would cost allot, if you bought the rounds say 8k for a 2k round then 2k second hand van, you might be able to put an employee on the road for 10k. I would take say 2 years to make that 10k again with the aid of the employee, bringing in 4k by my example, then you put on another. then one year with the aid of the two emploees bringing in 8k per year altogether, you now have three, 12 a year, then on the four year you have four bring in 16k, then on the fith year you have five employees bringing 20k.... Now you are taking on an employee every 6 months.
By that time you would need a heavy canvasing team.
I never said my figures were gospel, just that is isn't impossible.