Staying self employed is my ideal.
I think the average self employed person with excess money to spend will do 2 things.
Spend it all on kit and newer versions of that kit.
Throw it at other potential sources of income, which could become an even bigger business opportunity.
Window cleaning is a good base for checking out other business opportunities. It is cash rich and can easily be structured to nurse another opportunity through the early days.
Saying all that, i'm only window cleaning at the moment. But i consider myself in business, of which window cleaning is a part of that business.
And regardless of whatever else might come alongside, i also aspire to be cleaning windows when i am 70.