All Side Hustle Ideas
Services and freelancing

Whole-home water filtration sales

Selling whole-home water filtration systems to homeowners through Facebook ads that show the price upfront, with licensed plumbers doing the installs. The channel notes that this model can require a plumbing license, for example in North Carolina.

At a glance
Estimated by a classifier that read the source. The bar shows how sure it was.
Category
Services and freelancing
77% sure
x
Earns from
One-time salesLow confidence
53% sure
x
Startup cost (estimate)
$100 to $1k
61% sure
x
Time it takes (estimate)
Part-timeLow confidence
52% sure
x
Where
Online and in person
76% sure
x
Coding
No coding needed
99% sure
x
Source
The Koerner OfficeParker J. Smith, with Chris Koerner. “The Most Overlooked $81K/Month Business Anyone Can Start”, September 11, 2026
In their words, not verified by us$81,000 in monthly revenue 85 days after launch
Watch or read the source

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