My 2-cent:

With your budget, you'd get the most bang for your buck by buying from a private seller, especially when you pay in cash. Here are the main steps that I always follow:

1. Look for the cars you like on Kijiji Auto, filter out Private Seller only to eliminate all dealership options. I would preferred a Toyota (Corolla or Camry for sedan, and Rav4 for SUV) or Honda (Civic or Accord for sedan, and CRV for SUV) for their durability, especially at your budget level, and look for ones from 2011, 2012, 2013 and 2014. Later than 2014 you probably won't find anything in your budget.
2. If the post does not provide a CarFax report (it basically tells you all the important things about the car, i.e. how many owners, was it from out of province, was it a rental car, was it in any accidents, was it stolen, any maintenance record). I would avoid any car that was part of rental fleet, was in an accident that resulted in body frame damage, and oil change should have been done at regular interval (3,000Km for regular oil and 8,000Km for synthetic oil). It is not uncommon for the owners to not provide a CarFax report for this price range since it costs you money, in such case you can purchase one for cheap on ebay, just search for carfax report, it will be much cheaper buying the report directly from CarFax.
3. To avoid wasting your time and the seller time, when you find a car you like, do a research to determine the fair price for the car, just enter the make, model and year into these 3 website and get the average price https://www.autotrader.ca/valuations/
4. When you find something you like, arrange with the seller to view the car, best to meet up during daytime, at a parking lot large enough that you can drive around and get a feel of the car, just drive around, test the acceleration, the brake, full right turn, full left turn. It's best to turn off the radio so that you can listen to any strange noise that may indicate issues with the brake, steering wheel, suspension ...