This post is for those who have actually gone to and attended Blizzcon in the past.
What would be a realistic guesstimated budget to set for to be able to attend? Inc room and board, food, taxi, merch, etc. I live in the Midwest and am between lower to middle class.
I’m sure things have changed over the past couple years especially given the inflation of things.
i was at that convention in February for an unrelated event.
it’s not THAT expensive. Depends how much you drink.
you can rent a car at the airport instead of getting a taxi, like a normal person. 
and stay at a hotel in walking range.
hotel + car + parking is probably about $250-300/day and then food probably about $50 more? Depends, is it steak or McDonald’s? I’d say the whole thing can be ~$1500 if you’re not going big. airplane and car and 3 nights.
I’m not much of a drinker anymore. I did a lot of my partying while I was over seas.
Hotel: Blizzard has a hotel block noted HERE. The lowest price I see is Towneplace Suites by Marriott and Sonesta Simply Suites, both at $139/night.
Flight: A quick Google Search suggests the average flight cost from DSM to LAX is $304.85. Obviously you can look for better deals (I see round-trip for $281) or pay top-dollar for upgraded seats.
Car Rental: Looks like on Turo/Kayak you could find a sub-compat (like a Toyota Yaris) for as low as $35/day. Maybe $200-250 total with taxes and insurance? Taxi and/or Uber/Lyft might be less expensive… didn’t look at those.
Food: You can probably find something interesting and still inexpensive, or as someone else suggested there’s always McDonald’s. Here’s a Yelp listing although you may prefer a different resource for finding places to eat.
Merch: Look at prices of plushies and statues and other tangible stuff on the Warcraft Gear Store.
Haven’t gone specifically for the con. But I’ve been to disneyland a bunch. And they’re like right next to each other. There’s quite a few cheap options for hotels in that area. You also got places like Downtown Disney being preeeeeeetty near along with all the other restaurants like Denny’s near the park. For stuff like food I mean.