I've been reading previous posts on the subject and various guidebooks and am now thoroughly confused which to take when I'm in DC in early July. Basically I want the one that goes to the best areas and where you can hop on and off as many times as you like with the best guides. So advice please? I'm leaning towards the Tourmobile ones

Tourmobile is the King Daddy of hop on/hop offs in DC, I don't think you'll be disappointed. They are all over the city at peak tourist times. Also, they do a very nifty after-dark tour when the mouments are all lit up--very pretty and unique, even if you've seen them in the daylight. Have fun!

We are going to DC in a couple of weeks and your question about the hopon/hopoff tourmobile was one of the questions I have wanted to ask about.
Does anyone know the price of the day and or night tour.?
I went on their website and it doesn't tell how much.

We were pleased with the Tourmobile, but found that their routes were for the most part just the area between the Capitol and Arlington Cemetary. It didn't go to areas much outside the Mall, like Georgetown, Foggy Bottom, etc. But we had all-day Metro passes, so that didn't matter much.

At the time we used it (2 yr ago), they had a deal where if you purchased your tix after 1pm (or 2pm??), for only $2 more you got the next day too.

I haven't been on Tourmobile or the Old Town Trolley, but they're both pretty popular. I've heard that the Old Town Trolley (http://www.trolleytours.com/Washington.htm) takes you into more of the neighborhoods, including Georgetown and the Dupont Circle area. Also that the Trolley drivers/guides are more animated and give you more info than the ones on the Tourmobile. Even so, the Tourmobile (http://www.tourmobile.com/) would be good, too, as long as it goes where you want and you don't need a lot of frills, Tourmobile is pretty convenient. Then there's always the "DC Ducks" tours (http://www.historictours.com/washington/dcducks.htm)

One big advantage of Tourmobile would be that it's the only company allowed in Arlington National Cemetary - the others can only take you to the entrance. It's a pretty good hike to sites like Tomb of Unknown Soldier and the (Robert E.) Lee House from the main entrance. I think you can buy tickets for Tourmobile for *just* within Arlington, however.

I was the Old Town Trolley at several places in Georgetown, but we used the 50 cent (25 cent w/ Metro transfer) Georgetown Shuttle to get there from DupontC, Rosslyn, or Foggy Bottom. It's not a hop-on/hop-off service, and there's not narration, but it's darn cheap!

That should have been:
"I *SAW* the Old Town Trolley at several places"

I ma dyslexic at tiems!