Stephen Puddister's booth at the Home Renovations Show isn't offering the latest bathtubs, fireplaces or hardwood flooring. He's selling caution.

Ontario's Consumer Affairs Ministry has set up a booth at this weekend's event at Ottawa's Ernst and Young Centre with an aim to educate show-goers — especially seniors — about home reno scammers.

Puddister, a spokesman for the ministry, said the first rule homeowners must remember is to insist on a signed a contract with start and end dates, a complete cost breakdown and not paying upfront more than 10 per cent of the total value of the work.

"Any reputable home renovator has enough money to buy materials if they're going to do a renovation, so we recommend ten per cent down is the max that you should do," Puddister said.

Consumers also have 10 days to cancel a contract, and 30 days to recoup deposits if the contractor doesn't deliver, said Puddister.

Homeowners who don't have a contract for home renovations can end up with shoddy workmanship, like this roofing job.

Seniors Al Dunn and his wife Carol said they've hired many contractors over the years and never worried too much about the fine print.

"If was dealing with somebody that I thought was reputable, and they seemed like they were to me, I'd deal on a handshake. I always have," Dunn said.

Like Puddister, Mike Martin, chair of Canadian Renovators' Council and a local Ottawa contractor, said making a deal without a contract is a risk people should avoid.

Martin also advised that if you're thinking about making major renovations to your home, choose a contractor certified by Renomark.

Created seven years ago, Renomark compels members to abide by strict rules, including offering a two-year warranty on any work and carrying $2 million in liability insurance.

"With your written contract you're paying by a cheque or Visa, you're not paying cash. When you have a written contract, people are not going to run away and you won't get ripped off," said Martin.

"Whereas people who are not in the Renomark, they can just do shoddy work via cash and nobody's going to find them anywhere."

Martin said 75 per cent of contractors are not Renomark certified and are underground cash operators.

Paul Le Guerrier, sales director for the show, is touting consumer awareness and pointed to the Greater Ottawa Home Builders' Association's free consultation on how to hire a contractor.

He also offered a few basic rules to follow.

"If you're going to be dealing with a contractor, these are the steps you should be going through — make sure you're getting background checks, you're getting referrals, you're checking with the Better Business Bureau. Before you sign on the dotted line," he said.

The Home Renovations Show runs from Jan. 18 to Jan. 20 at the Ernst & Young Centre, formerly the CE Centre, at 4899 Uplands Drive.