I would HIGHLY recommend that you plan to meet up with some people before you go. Have you done solo trips before? Do you know what you're comfortable with?
I did a 16-day solo trip to Europe recently, and I would have come home early if I were by myself the WHOLE time. I do love my "me" time, but it gets very isolating. Of course you won't have the language barrier, so that is a plus. I spent my first 3 days completely solo at
Disneyland Paris, and I was SO happy to see my tour group on the 4th day, even though they were all strangers. I was with them for 7-8 days (had some solo time interspersed (sp?)) and then ~4 days solo at the end in Paris. I found myself getting very lethargic on my final solo days. The excitement of the trip had worn off, and being practically mute in a place where I didn't speak the language well was getting old. I was in much better spirits when my tour group was in town, even when I was off by myself. It's comforting to know you have somewhat of a support structure in the area.
Also, hotel pricing in the U.S. is different than in Europe. The cost is usually the same for one or two people. Most rooms will have 2 double or queen-sized beds, but you can ask for a room with just one bed if available. Single beds are virtually unheard-of. The price is usually the same for one bed or two, as long as there aren't additional people staying with you (they usually charge a small fee per person over 2). So, I like to get 2 beds so that I can keep all of my junk on one bed and sleep on the other, since i'm messy.