We're off to Vienna Tuesday for two weeks. We've been looking at some youtube videos and a friend loaned a Rick Steve's book. I have tours scheduled the first week, one is an all day private tour the third day to get a better feel for the place, hopefully. We did this in Tokyo and Seoul and had a great experience.
I checked prices from here to Spain in July, Holy Moly, $3K for comfort. I'm more used to around $1.3K to Europe, but we don't usually go in July and August.
Vienna will be on the cool side for us, into the 40s at night some, 60s in the day. I was able to use points for the entire stay at a Hilton. It's not the perfect location but was a lot cheaper than the "downtown" Hilton and it's on the river.