I find pricing for OW courses to be somewhat opaque. A lot of places advertise a price that excludes things that are *not* optional costs. They also exclude certain things that may be technically optional, but that you will want. Because different shops' advertised prices don't all exclude the same things, it's difficult to comparison-shop even just on price, let alone if you're trying to assess actual value.
(ETA: Value is especially hard to assess because few people writing reviews have any basis for comparison. If you go looking on Yelp for a good burger, you'll see lots of opinions by people who've eaten lots of burgers and know what they're talking about. But how many people take more than one OW course? So when you do decide, pay it forward--you'll be unusually qualified to tell others how your course was compared to the first one you did!)
When I decided to get certified, I initially picked a local shop that listed a course price of about $800. But I was doing it with a friend, and she blanched at that price. Instead she did a little shopping on Groupon and found another shop advertising a price a little over $200 per person if we bought together. So we went with that. But it turned out that price didn't include the book (another $25), the rental gear (another ~$200ish, IIRC), or the personal gear we had to purchase (mask, fins, snorkel, booties; I bought the cheapest ones they had that fit and it still came to around $600). The rental gear did not include a hood or gloves (which in retrospect I could've really used), nor any signaling devices (which the coursebook said we had to have, so I shelled out for them), nor even a bag for the gear (which I also ended up buying from them). The plan was for us to do all our OW dives at the beach, but when conditions were looking poor, we had to decide whether to postpone indefinitely (meaning I wouldn't be certified in time for my vacation) or charter a boat. I managed to convince everyone in class to shell out another ~$150 plus crew tips so we could finish the course on time. I never did confirm exactly what that other $800 course did and didn't include, but I've seen other courses advertised that do a better job spelling out what they include, and it's by no means universal.
If you feel confident that you know how to dive and you just want the cheapest possible C-card, and if you're willing to drive a bit, I believe Pacific Wilderness in San Pedro offers the lowest total cost. They also have classes going on almost constantly. It's not bad instruction, from what I can tell, just done quickly, as most shops do. There's a higher caliber of instruction available at a significantly higher price, but it takes some doing to find it. Going with a GUE course might be the surest way to find it, though there are other options.
Anyway, if $500 ends up being the total price you have to pay, I'd say that's pretty good. Enjoy!
