How This Side Hustle Started Three Years Ago
About three years ago, I launched a side hustle designing retaining walls for residential clients.
In California, any retaining wall that holds back more than four feet of soil requires a permit and a design completed by a licensed professional engineer. That requirement alone creates a small but very real barrier — and that’s where I found my niche.
Instead of chasing broad engineering work, I focused specifically on residential clients who needed compliant designs but didn’t want to deal with large firms.
Finding a Niche in Residential Engineering Design
Most homeowners don’t realize they need an engineered design until they’re already mid-project.
That gap created steady demand for:
- Retaining wall design calculations
- Engineering drawings
- Assistance with plan submittals and permits
By positioning myself as someone who handles the entire design and permit process, I made it easier for homeowners to move forward — and easier for me to get consistent work.
What I Charge and How Much It Makes
At this point, the numbers are very predictable.
I typically take on one to two projects per month, which reliably generates $1,000–$2,000 in monthly side income.
My pricing structure looks like this:
- $250 per hour
- $500 flat fee, plus any material-related costs
Last year alone, this side hustle brought in roughly $18,000 — without heavy time investment.
What the Work Actually Includes
For each project, I provide:
- Structural design calculations
- Engineering drawings
- Support with submitting plans and pulling permits
It’s straightforward, repeatable work that fits cleanly into limited free time.
How I Get Clients Without Paid Advertising
Most of my marketing is organic.
New clients usually come from:
- Word of mouth referrals
- Facebook Marketplace
- WhatsApp and Nextdoor groups
I’ve never relied on paid ads. Local visibility and trust do most of the work.
Why I’m Keeping This as a Side Hustle Only
Even though I enjoy the work and it’s an easy way to make extra money, I have no interest in turning this into a full-time business.
I deliberately:
- Stay within the residential space
- Work only in spare time
- Limit myself to a handful of total hours per month
For me, the value is flexibility — not scaling, hiring, or chasing growth.
Final Thoughts After Three Years
Three years in, this side hustle does exactly what I want it to do:
- Generates predictable extra income
- Requires minimal time
- Stays low stress
- Fits cleanly around the rest of my life
Sometimes success isn’t about going bigger — it’s about finding something niche, controlled, and sustainable.