A few suggestions... There's a Restoration Hardware outlet at the Tulalip Outlet mall so you might find a few deals there. ( I remember you mentioned living in Edmonds, so it might be worth the drive up north.) Or, as Babs suggested, having a glass and mirror shop custom make a nice beveled mirror is very reasonable. When we remodeled our master bath we made a frame with some nice trim/molding that we bought from our cabinet maker (to match our cabinets) and had a mirror with an extra large bevel to fit in the frame. For our guest bathroom I found a simple, wide, solid wood, oversized picture frame at Aaron Bros. on sale for $20, and a local glass shop put a beveled mirror in it for me for $40. It looks fabulous! (We used a metal bracket called a hangman which makes it easy and safe to hang large, heavy objects.) In regards to the size, personally I think bigger is better, especially vertically. I've always noticed nicer hotels have wonderfully large mirrors - they really add a feeling of spaciousness to what are usually small rooms.

I have two vanities from Costco and have been very happy with them. I don't think you can go wrong with Costco, but I would recommend reading the product details closely when making your selection. I bought the 36" Covington about 2 1/2 years ago for my powder room, though the granite is different from what they're selling now. The granite is thick, came with three backsplashes, and the drawers and doors are all self close. You can see from the weight the vanity is very heavy. Overall, it has a very solid, high quality look and feel to it. In contrast, the other vanity I bought (not on the Costco site) has soft close only on the doors, came with just one backsplash, the granite is 1/2" thick, and weighs much less. I'm happy with it, but it doesn't have as high end feel to it as the other one.

I think, even though it is a weight bearing wall it can be recessed so long as wiring doesn't interfere. You need to frame it in with a header, much like a window in an outer wall. And depending on the wiring situation, if it isn't right across the centre, it maybe could be moved above or below the mirror opening. Just a thought. We are just re-doing our bathroom and had a surface mounted 36 inch medicine cabinet until now. We are gutted to the studs and found the vanity wall to be a 6 inch wall because the stack is in that wall. So our contractor just cut into the 2 x 6's part way (about 4 inches) and framed it In with a 2 x 4 header and frame. We just bought a 40 inch Kohler tri view cabinet. It has soft close doors and seems like a very nice one but it was not cheap. We didn't find many 40 inch tri view ones so chose to pay for the Kohler brand. It does have mirror inside and out and a sliding magnifying mirror inside the centre door, which might come in handy since the mirror will be farther away now with being inset.

My daughters kitchen is about ten years old and it looks great, she has Candlelight Cabinets. When I did my kitchen remodel two years ago I went to a distributor that sold them. The kitchen designer was excellent and every vendor that worked on my kitchen commented on how nice the cabinets are. My contractor said it was the first time he had every cabinet come out of the box fully square and the paint finish was perfect. Two years later, they look the same as when they were installed, I highly recommend them.