How to Vet a Renovation Contractor: Complete Checklist for GTA Homeowners

After 50+ years and 30,000+ renovation projects across the GTA, here is the checklist LF Builders recommends every homeowner work through before hiring any contractor.

Step 1: Verify Credentials and Insurance

Request these before the quote — not after you have fallen in love with their pitch:

  • WSIB Clearance Certificate — Protects you if a worker is injured on your property. Verify the clearance number directly at wsib.ca.
  • Certificate of Insurance — $2M+ commercial general liability minimum. Ask to be named as an additional insured on the certificate for the duration of your project.
  • Business registration — Verify they are a registered Ontario business via the Ontario Business Registry. Registered business means accountability and a paper trail.
  • Trade license numbers — ESA license for electricians, Ontario plumbing license for plumbers, TSSA registration for gas fitters. Ask for the number; look it up yourself.

Step 2: Review the Written Quote

A proper quote is not a lump sum. It is a line-item document.

  • Scope of work with material specifications (brands, grades, dimensions where relevant)
  • Line-item pricing for labour and materials
  • Confirmation that permits are included and will be pulled in the contractor’s name
  • A clear statement of what is and is not included

If a contractor gives you a one-page lump-sum quote with no specification, you cannot evaluate it and you cannot hold them to it.

Step 3: Know the Red Flags

Walk away from any contractor who:

  • Asks for more than 15% deposit upfront (10% is the GTA industry standard)
  • Refuses to pull permits (“permits just cause delays” — this creates liability at resale)
  • Pressures you to sign the same day or claims the price is only good today
  • Insists on cash only with no paper trail
  • Cannot provide a physical business address
  • Pushes a vague scope with no line-item pricing

Step 4: Review the Contract Terms

Before signing, confirm these terms are present:

  • Milestone-based payment schedule — payments tied to specific completed stages, not calendar dates
  • 10% holdback — held until substantial completion AND all deficiencies corrected and signed off
  • Written change order process — any change above a defined threshold requires a written change order before work proceeds
  • Warranty terms — minimum one year on labour; material warranties passed through from manufacturer in writing

A contract that protects you is not unusual — it is standard practice for any reputable trade.

Step 5: Call References Directly

Phone, do not email. Ask:

  • Did they pull all required permits and pass inspections?
  • Were there change orders? How were they handled?
  • How did the contractor communicate when there were problems or delays?
  • Would you hire them again without hesitation?

One reluctant “yes” on that last question is worth more than ten enthusiastic ones.


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