The kit is not a cheaper version of the professional floor. It is a different product, at about a tenth the film thickness, on a surface that was never opened.
The Price Gap Is Real, and So Is the Reason
A kit for a two-car garage runs $200-$600. A professional floor runs $4,000-$6,000. That is roughly a twelve-times difference and it deserves an honest explanation rather than a sales pitch. The gap is not margin. It is film thickness, surface preparation, and about $30,000 of grinding and extraction equipment.
What You Are Actually Buying in a Kit
Consumer kits are typically 40-50% solids water-based epoxy. That means half the volume evaporates as it cures, leaving a film in the range of 2-4 mils, about the thickness of a coat of paint. A professional system is 100% solids epoxy with a flake broadcast and two polyaspartic coats, landing at 25-35 mils. That is not a better version of the same thing; it is an order of magnitude different.
The Prep Is the Real Gap
Every kit includes an acid etch packet, because acid is cheap and grinders are not. Etching produces an inconsistent surface profile, cannot remove contamination or old coatings, leaves salts behind if the rinse is imperfect, and does nothing about flatness. A professional install starts with a planetary diamond grinder and HEPA extraction, opening the slab to a measured CSP 2-3 profile. That single difference decides most of the outcome.
What Happens Around Month Fourteen
The predictable failure is hot tire pickup. A car that has been on the highway comes home with hot, soft tires; plasticizers migrate into a thin coating; and when the car pulls out, the floor comes with it in a perfect tread pattern. The second failure is edge lifting where a chip has gone through to concrete and moisture has got underneath. Both usually show inside two seasons.
When DIY Genuinely Makes Sense
Two cases. A concrete sealer or lithium densifier. No film, hard to get wrong, and it stops a slab dusting for around $1 per square foot in materials. And a purely cosmetic short-term fix on a floor you are about to sell or a shed you do not care about. If the objective is a floor that is still there in ten years, a kit is not the cheaper route to it. It is a detour that costs more.
The Cost of Getting It Wrong
Removing a failed kit adds $1-$3 per square foot to the eventual professional job, because grinding through a partially bonded film is slower than grinding bare concrete. On a two-car garage that is $500-$1,500 on top of the original quote. The $400 experiment ends up costing more than the professional floor would have.
Want a real number for your floor?
Free site visit with a moisture reading, and a written fixed price. Across the BC Interior.