Pressure washing business and similar ideas...Do these kinds of ideas realistically work?

I've seen heaps of posts over the years about stuff like:

• Starting a pressure washing business
• Starting a bin washing business
• Starting a dog poop cleanup business (lol)

These sound great on paper, but I'm wondering if anyone knows anyone actually making money with these simple service businesses.

I guess the posts I see make it sound so simple...Like buy a pressure washer, knock on a few doors, and BOOM you're making money 😂

I'd love to hear from someone actually doing this if you have info about getting your first clients, closing rates, and how difficult or easy these kinds of businesses actually are.