Here's what happened. We told her that we'd reach Vancouver by 3 PM. However there was traffic on the way and my father couldn't drive that well in Vancouver. He told us that we'd be late. We were busy guiding him by GPS and he was so used to the right hand drive in India that he got confused in the city. It was really easy everywhere else because of the low traffic, but we reached the homestay 2 hours late. We reached at 5 PM. The lady had been waiting but she had prior commitments and she had to go. She would have given us the key to the house or left it under the doormat if we would have paid before, since we hadn't paid, she couldn't leave the key or give us the passcode. We waited for around 45 mins outside the house and she didn't come.
It was really difficult as we were waiting outside the house with our luggage. We learnt that punctuality was important but also that it was really important to pay by card to prevent hassles. The website does always ask to pay by card but if you get in touch with the owner, they may allow you otherwise. However, it is not a great idea because you could end up in a similar situation.