If you get a scratch-and-win game card in your mailbox like a lot of other Calgarians, chances are you're going to be a winner.

But there's a catch to claiming your prize.

You'll have to sit through a product demonstration and a sales pitch.

And CTV has found out the company behind the cards is the same one behind the water test phone calls we exposed last month.

Charlotte Evans got a card in the mail, scratched off three 7s and thought she'd won a laptop.

But when she called in to claim her prize, she was told she didn't qualify because she rented, and didn't own her home.

Angela Apuzzo owns her home, but when she called in to claim her prize, she was told she had to have a test done on her tap water first.

Apuzzo agreed to the test, but then called back to cancel.

Just looking at the scratch cards, it's not clear who's giving away the prizes or why. You're just instructed to call the contest hotlines if you win.

Consumer specialist Lea Williams-Doherty called both hotlines, posing as a winner and discovered that it's Star Industries behind the cards.

The company has been in the door-to-door sales business for years.

Charlotte's card rang up Tristar, the company's vacuum cleaner sales arm.

Angela's card rang up Simple H20, Star's water filter sales arm.

Just last month, Lea discovered it was the company behind strange phone calls Calgarians were receiving.

People were getting calls from an outfit seeking to test the water in their homes. Many assumed it was the city on official business.

In fact, it was Simple H2O trying to sell them a $3,000 water filter system.

The owner of Star Industries Calgary, Dave Gold says the scratch cards and products come from the head office in Ontario. He's an independent distributor.

He says renters don't qualify for the in-home demo, but Charlotte could claim her prize at the office, though it may not be the laptop.

And about the water test, Gold said the company isn't implying the city's water is bad, it's just demonstrating an alternative to bottled water. Gold also denied that his sales force uses high pressure sales tactics.