Adding further to the thread if you search for Atrium Inn from May 10 to May 12 (2 days booking on the day of) you'll notice the original price is about $150 but is now $77 CAD.

I haven't stayed at this hotel before in Vancouver but it was a former Holiday Inn converted to the Atrium Inn. Reviews seem to show it's relatively reliable. Another hotel you can check out is Comfort Inn downtown with breakfast included (it's located across a hostel but the rooms are generally clean and breakfast acceptable). You're also RIGHT downtown, literally on the Granville Strip and 5 minutes walk to Canada Line station. Great location. They have deals going on occasionally; not likely with summer though.

I'd suggest you go for an Airbnb entire apartment though; the deal there is likely better. If you can make it out to Coquitlam there's Sleep Lodge which is a really crappy motel but $420 CAD/week (check craigslist). Then there's the Coquitlam executive Inn which is a 3.5 star hotel that's acceptable and costs about $120/night regular price. It's an Expedia VIP plus hotel so you get some extra gifts booking through Expedia with Expedia Gold. It's a reasonable good hotel.

Finally, if you're out of options, go to UBC. There's St. Andrew's residence that rent out during the summer for $110/studio. Old rooms but you're surrounded with great views.