Payments for Dock & Door Contractors: What Stripe, Square, and the Big Processors Actually Cost You

The short version: dock and door is commercial, which changes the payments math in your favor — if you know the two things residential shops don't: ACH for contract billing and Level II/III interchange for commercial cards. A $1,305 emergency invoice paid by ACH costs $5; by card it's ~$38; and the facility manager paying with a corporate card can cost you less than a residential card if the transaction carries the right data. Here's the math at your ticket sizes, with published rates checked October 2026. Also see Dock & Door, AI for Dock & Door Companies, and Tech for Dock & Door Companies.

The fee table: what each processor actually charges you

Published rates, checked October 2026. Square: 2.6%+$0.15 in-person, 2.9%+$0.30 online, 3.5%+$0.15 keyed/stored. Stripe: 2.7%+$0.05 in-person, 2.9%+$0.30 online, 3.4%+$0.30 stored. Interchange-plus (typical ISO contractor pricing): ~0.3% markup over interchange.

$1,305 emergency service (card on-site): Square $34.10 · Stripe $35.29 · Interchange-plus ~$28.70 · ACH (0.8%, capped at $5) $5.00

$1,305 emergency (corporate card, Level II/III data): Square $34.10 (no Level II/III benefit) · Stripe $35.29 (no benefit) · Interchange-plus with Level II/III ~$24

$4,200 dock leveler repair (invoice): Square $122.10 · Stripe $122.10 · Interchange-plus ~$92.40 · ACH $5.00

$12,000 PM contract, annual billing (invoice): Square $348.30 · Stripe $348.30 · Interchange-plus ~$264 · ACH $5.00

$28,000 dock equipment install (invoice): Square $812.30 · Stripe $812.30 · Interchange-plus ~$616 · ACH $5.00

$812 versus $5 — same $28,000 install. The Level II/III row is the one nobody's generic page explains: commercial cards carry higher base interchange, but submitting Level II (tax amount, customer code) and Level III (line-item detail) data qualifies the transaction for lower commercial rates — typically 0.50–1.00% less than the same card without the data. Square and Stripe's flat rates don't pass any of that through; interchange-plus processors do. On a $4,200 corporate-card payment, that's ~$20–$40 per transaction for filling in fields your invoicing software can fill automatically.

At volume: $1.5M a year in contract and service billing. Card at flat rate: ~$43,500/year. ACH where possible + interchange-plus with Level II/III where card: ~$12,000–$18,000/year. The rails are the same — Finix builds that payment infrastructure; the difference is entirely in how the pricing passes through.

The workflow checklist the big processors fail

• Contract billing on ACH. The $12,000 annual PM contract bills by bank transfer — $5, not $348. Commercial customers expect ACH; offering it is table stakes, not innovation.
• Net-30 that actually collects. Half your commercial invoices go net-30. The workflow: invoice with ACH instructions prominent, automated reminders at 15/30/45 days, card as the "pay now" fallback. The processors' pages assume card-first; commercial is ACH-first.
• Level II/III data on corporate cards. When the facility manager insists on the corporate card, the invoice carries the tax and line-item data that earns the lower commercial interchange. Flat-rate processors can't do this at all.
• Emergency billing at the emergency rate. The after-hours invoice goes out the same night with the premium applied — the voice-to-invoice flow handles it, and the payment link rides along.
• Deposits on installs. 50% down on the $28,000 dock equipment before you order it — ACH or card at the proposal signing.
• Surcharging — commercial rules differ. Surcharging commercial cards has its own rulebook (and many B2B contracts prohibit it). Check the contract before the card-brand rules — the customer's purchasing agreement outranks your surcharge program.
• Multi-location billing. One customer, six warehouses, one invoice with per-location line items — or six invoices. Your invoicing has to do both, because facility managers ask for both.

Square's pages assume a customer with a card. Your customers have AP departments. Different species.

The honest verdict on each processor

Square: wrong tool for commercial. Flat rate can't pass through Level II/III savings, the aggregated-risk model hates $28,000 invoices, and nothing about it speaks AP department. Keep it far from the contract business.

Stripe: the API can do invoicing, ACH, and webhooks — but Level II/III optimization and commercial workflows are custom builds. A developer's processor, again.

Adyen: actually relevant here — enterprise interchange-plus with real Level II/III support. But enterprise-shaped sales and minimums; a $2M dock-and-door shop is small for them.

Chase Payment Solutions, Fiserv, Global Payments/Worldpay: this is their home turf — commercial interchange-plus with Level II/III, ACH, and bank relationships. Their pricing fits; their onboarding doesn't know what a dock leveler is, but the product is right. Get the quote, bring your own workflow.

The commercial answer: ACH-first for contracts and installs, interchange-plus with Level II/III for the corporate cards you can't avoid, net-30 discipline with automated reminders. The residential processors aren't just expensive here — they're the wrong species.

How a dock & door company actually wires this up: notes from Finix's public docs

ClaroPro handles voice-to-invoice — the emergency gets dictated at the dock and billed the same night. The money movement is where Finix's public docs (docs.finix.com) get commercial. What to look for:

• ACH for contract billing. Bank-transfer guides with the $5-cap math — the $12,000 annual contract that should never see a card fee.
• Fee profiles with Level II/III. Their fee-profile documentation covers interchange-plus structures — the mechanism that passes the commercial-card savings through instead of pocketing them like flat rate does.
• Invoicing with line-item data. Docs on invoice structures carrying the per-location, per-line detail that qualifies corporate cards for Level III rates.
• Webhooks for AP workflows. Payment events that feed the customer's AP expectations — paid, pending, failed — so the facility manager's system and yours agree.
• Identity verification for big tickets. Onboarding docs covering the KYC that lets you take $14,000 deposits without the freeze roulette.

Architecture, not brand: ACH-first contracts, Level II/III on the unavoidable cards, net-30 with teeth, money events feeding the service history. That's a commercial payments setup.

FAQ

What are Level II and Level III interchange rates? Discounted card rates for commercial transactions that carry extra data — tax amounts and customer codes (Level II), line-item detail (Level III). Typically 0.50–1.00% cheaper than the same corporate card without the data. Flat-rate processors don't pass it through; interchange-plus ones do. Rates checked October 2026.

Should commercial customers pay by card at all? Only when they insist — and then with Level II/III data attached. Default everything to ACH: $5 flat beats every card rate at commercial ticket sizes.

How do I collect net-30 invoices faster? ACH instructions on the invoice, automated reminders at 15/30/45 days, and a card "pay now" link as the fallback. The reminder sequence does more than any processor choice.

Can I surcharge commercial cards? The rules are stricter and many B2B contracts prohibit it outright. Read the customer's purchasing agreement first — it outranks the card-brand rules.

This month: move contract billing to ACH, turn on Level II/III data for corporate cards, and put automated teeth behind net-30. Then read Tech for Dock & Door Companies — the contract system is what makes the payment discipline possible.