Okay, Hawaii person here!

I've lived in Hawaii my entire life. It is expensive when you compare it to other areas of the U.S., but I guess since I've lived here my whole life, it doesn't really phase me much (except when I go to a grocery store somewhere else and see how low the prices are!)
Will you be receiving any type of housing or cost of living allowance? The median price of a home in Hawaii is about $600,000. You could get a townhome or a condo for $300-$400K. I'm a renter, and our 3/2 duplex is $1600/month, and that's considered low. I consider myself lucky.
I went to the grocery store yesterday, and I paid $2.28 for a carton of milk (the one right below a 1/2 gallon -- can't remember if it's a liter?), 50 cents for a can of tomato sauce (on sale), $2.89 for a dozen eggs, and romaine lettuce was $1.49/pound.
Pearl Harbor is central to a lot of things -- would you be living in the area as well? There are lots of places to choose from that would be convenient to Pearl Harbor. House? Condo? Salt Lake is very close to Pearl Harbor, and there are a LOT of condos in the area.
Although things are expensive here, the people (for the most part) are generally very friendly. Tax is low, we don't have a true "sales" tax, but I won't get into that right now -- basically, when you buy stuff, you'll get charged about a 4.167% tax. I think movies are cheaper here, about $8. And the beauty! You could go to the beach or go hiking every weekend. The weather is generally very good since we don't experience extremely cold temperatures. You could fly to a neighbor island for the weekend.
There actually is NOT a Super
Walmart -- they're considering building one, but it hasn't happened yet (at least not on Oahu). We have several Costco's, including a Costco gas station -- which reminds me, the average cost of gas right now is about $3.25 on Oahu, and we have a couple of Sam's Clubs (my club of choice). We do NOT have an IHOP or Olive Garden, but we have lots of other great eateries to suit all tastes and budgets.
Anyhow, this is just an overview. Feel free to ask more questions or to PM me if you have more specific things you'd like to know about.