I see 2400 in wages and possibly over 6k in revenue a week.... Plus expenses I think he would pretty good, certainly not bankrupt.
As for the OP I found that fall cleanups are HUGE money makers when it comes to the season as a whole. If you can't mow anymore lawns a day then don't take on anymore as long as you are living okay. Fall cleanups are good because I can usually do 2 a day and make double of what I make mowing in a day by far with less overhead. I don't have a leaf loader or a dump trailer just built sides on my trailer and truck and stuff em and dump em. Having a helper is a must though, and so is a big wb blower. Apps are another thing that I see huge money being left on the table for my company. I would like to get my license and begin to do apps and that can add to your revenue aswell.