Driving in and out could present a problem if the street is so close to the entrance that you are still negotiating a turn while you are entering the garage opening.
I believe the Honda Odyssey is about 6 1/2 foot wide. If you can park it well over to the right side of the garage, you'll have enough room to open the driver's door to get in and out, but being off of the mark could make it difficult.

Modern homes often have "two car" garages with widths of around 20 feet. In my opinion, that is stretching the term two car a bit, but people get by with them.

A ten foot wide tandem garage should be acceptable for small cars, if it really will be ten foot wide on the inside. I'm not sure what you plan to build with, presumably block, but the walls take up some space. I suggest that you do detailed enough planning to determine what kind actual interior dimensions you can expect.

As a child, I lived for awhile in a house with a tandem garage. We had a workbench at the far end, and the car lived at the door end. We had a side entrance just past the midway point, which was an ideal location for how we used the garage. The people door location makes a big difference in how usable a tandem is. It's worthwhile to put some serious though into where to locate it.

If you can't get your car into a 9 foot garage without banging the sides, you really shouldn't be driving. Since Hummer is no longer in production, and you live in a city where a Ford Excursion would be a nightmare, I would go for it (with the caveats mentioned).

The other thing to think about is whether having two cars parked in a row will be too much of a hassle. It means you have to remove one to remove the other. Obviously you can deal with that, but it may create a hassle.