About us
A family-run bookkeeping and payroll practice in Covina, California.
Our story
Square One, All Business is run by a brother and sister in Covina, California. Karla does the books and the payroll; Christian builds the systems that keep the work organized, secure and on time.
We started this practice because small business owners kept telling us the same thing: the big services are hard to reach, and the cheap ones are software with a support queue. We wanted to be the other option — a real person who explains your numbers in plain English and answers when you write.
The name says what we believe. Wherever your books are today, this is a fresh, honest starting point. It starts here.
We’re veteran-owned — Christian served in the United States Marine Corps — and family-run.
The team
Christian Carbajal
Co-owner · Systems and operations
A business analyst by trade and a Marine Corps veteran. Christian builds and runs the systems behind the practice — the tools, the file structure and the security — so the bookkeeping stays organized and your information stays protected.
Karla Carbajal
Co-owner · Bookkeeping and payroll
Karla holds a bookkeeping certificate and a payroll specialist certificate, and does the hands-on work: categorizing, reconciling and running payroll. Plain-English answers, no jargon.