How I Learned to Calculate the Real Cost of Office Renovation Materials (And Why the Lowest Quote Cost Us $3,000)

When I took over purchasing in 2020 for a 150-person architecture firm, I thought I knew how to compare prices. Get three quotes, pick the lowest, right?

That theory lasted exactly one renovation project. We needed new breakroom counters and a reception desk. I went with the lowest bid for Cosentino Silestone—a beautiful quartz. The final cost was nearly 30% more than the ‘expensive’ quote. I had to explain that to my VP.

Here’s the checklist I now use to calculate the true total cost of any surface material purchase. It’s saved my budget—and my reputation—more than once.

Who This Checklist Is For (And When to Use It)

This is for anyone managing a commercial fit-out, a lobby refresh, or a multi-station office kitchen. You’re comparing quotes for quartz, Dekton, or marble. The project involves fabrication and installation, not just buying slabs off a lot.

If you just need a single vanity top for a home powder room, a lot of this is overkill. But for anything business-related—where delays mean unhappy staff and reprints mean lost days—use this.

Here are the 6 steps I follow now.

Step 1: Isolate the Base Material Price (With a Catch)

This sounds obvious, but the trick is getting the grade right. A quote for Cosentino Silestone in the classic ‘Calacatta’ color might be $X per square foot. But what grade? Cosentino has different series (Classic, Lagoon, etc.), and the price jumps significantly.

I ask for the exact product code. I once got a quote for ‘Silestone’ that was actually for a discontinued color—the fabricator was trying to use up old stock. (Should mention: the new color we eventually chose cost 15% more.)

Step 2: Factor in Slab & Sink Coordination (The Hidden Surcharge)

Here’s something vendors won’t tell you: the base price on a sink might assume you’re using a standard drop-in model. But if you’re integrating a Cosentino ‘NeoLit’ seamless sink system, which is a key advantage for their Silestone line, the fabrication changes.

For our project, the integrated sink solution added a premium for:

• Laser-cutting the sink opening with specific tolerances.
• Reinforcing the edge (Dekton needs this for thin-edge sink mounts).

I went back and forth between an undermount sink and the integrated system for a week. The integrated looked better for the reception desk (ug, the seams on a traditional undermount). The cost was $400 higher. I chose the integrated because the total look was critical for client-facing space.

Quote check: Ask if the sink is included in the base price or if it’s a quoted add-on.

Step 3: Don’t Forget the Sealing & Edge Profile

This is the step most people ignore. Your fabricator will offer standard edges (bullnose, bevel) at one price. A custom ‘ogee’ or ‘waterfall’ edge costs more. Also, while quartz and Dekton are non-porous, natural stones like marble or granite require sealing. Some fabricators include the sealer, some do not.

Our first quote was $5,000 for the material. After we specified the custom ‘pencil’ edge profile for the breakroom island, it went up to $5,800. The $4,200 quote from a different shop? They had no edge profile listed. That was a red flag.

Action: Get the edge profile written into the contract. And ask if sealing is included.

Step 4: The Delivery & Site Access Fee

Delivery isn't just 'shipping.' For a large piece of Dekton (a 126-inch slab), you can't just toss it in a van. You need a truck with a lift-gate, and possibly a team to bring it inside. If your office is on the 10th floor and the elevator is small, you might pay extra for ‘hotel’ or ‘stair’ delivery.

In our 2024 project for a 3-location office consolidation, one vendor quoted ‘free delivery.’ I asked what that meant. It meant curb-side drop-off. The cost to get 4 slabs of granite up to the 2nd floor via stairs? An extra $750. Surprise, surprise.

Pro tip: Ask for ‘inside delivery’ pricing. It’s usually an extra $150-400.

Step 5: The Installation Contingency (Aka, The 'Oops' Fund)

No one plans for a slab to crack. But it happens. For our reception desk, the fabricator dropped a corner of the Silestone slab. Total bill for a replacement? $800, plus 3 days of delay.

Looking back, I should have insisted on a ‘Right of First Refusal’ clause—where the vendor provides a backup slab at a reduced rate if the first is damaged. But given what I knew then (nothing about slab handling), I didn't.

Set aside 10-15% of the total quote as a contingency fund.

Step 6: The Total Cost of Ownership (TCO) Calculation

After all that, I add up everything:

• Base Material + Sink Premium + Edge Profile + Delivery + Contingency

On a recent bid for a Dekton floor in a high-traffic hallway, the lowest quote was $12,000. The mid-range quote was $14,000. The high quote was $17,000.

After applying my checklist:

• Low quote: $12,000 base + $2,000 (missing sink integration) + $1,500 (no edge profile) + $1,000 (delivery + stairs) = $16,500
• Mid quote: $14,000 all-inclusive = $14,000

The mid-range quote was actually cheaper. I went with them. That $3,000 lesson from my first renovation paid for itself.

Common Mistakes I’ve Seen (And Made)

• Skipping the site visit: Your fabricator should measure. If they won't, someone else will get it wrong.
• Assuming standard backsplashes: A full-height backsplash (counter to ceiling) costs 3x more than a 4-inch one.
• Not verifying the sealer warranty: For certain granite colors, if you seal it yourself, the manufacturer voids the stain warranty.