Personal preference. I prefer to pull in/out of the bigger door, even with the 2nd car there. The single side, I didn't like and therefore don't use (we have 1 single and 1 double). You'd get used to the single door, though, if that's what you want to do. If you're worried about the feel of it, can you try one out--maybe a friend's house that has one?

I much prefer two doors, and it's better yet if they have a pedestrian door between them for added space. We had XL "single" doors separated that way at a previous house and I loved that set-up. It does require planning, as the typical garage plan is too small.

I always back into the garage, so backing out is never an issue. The higher the home price, the more likely there are to be multiple doors rather than a single one. IOW, one door is cheaper than two.

Other considerations. With multiple doors, you don't have to expose all the contents of your garage to passersby every time you enter or leave the garage. A single door puts greater strain on the opening mechanism, or your back, if it's manual door, than multiple doors.

We have a bit of a tight garage situation (the turn around area is tight, that is), so we did one double door, and one single door. My husband will use the single door side, and will back into it (more than likely).

Recent thread on this but 2 doors more expensive, look better and are harder to get in and out of. Having never had them before, I'd go with a single big door or budget some money for paint.....Rubbing compound usually solves the car side of things.

We added length to our three car garage (main level) pre-construction. Went as deep as we could without changing the roof pitch. Many architects/designers don't put enough space between doors, therefore less space inside the garage. We also do not have any poles inside the garage, which is more expensive but well worth it. We can walk all the way around our vehicles (with the exception of DH Tundra which is pulled to w/in inches of the front wall - we can walk behind it) and don't have to worry about bumping cars or squeezing in/out of them.

Our garage doors are 9 feet wide with 2 feet in between the doors.

Two doors look better hands down.

One large door can make the space more useful. Say you need to do some work on the vehicle. You can pull out the other side and park in the middle to get around.

A large single door also allows my DH's grandparents to park in the middle so they can easily get his grandmothers wheel chair out and her in it.

I agree with everything lyfia said. My last house had two single doors. At first this was what I wanted as I preferred that look. After living with them for 6yrs. I would never choose that route again. I always found myself wishing I had a single double wide door. On my new house I have a 16ft. side facing door. I am much happier with this choice.

In my limited experience, the choice depends primarily on the ability of the owners to drive automobiles especially in reverse. I would assume the worst case and use one door but I would design it to look like two doors. I would post a photo but I am too lazy at the moment. (lazy = excessive wine consumption from being left alone for the evening by my family)

For me it is more of a convenience issue than a lack of driving ability. Being able to pull one car in the center to rotate tires or open all of the doors wide to vacume the interior was my concern.

Clopay has several examples on their website. It certainly confirmed our decision to have one large door and a 2nd door for the real vehicle - our golf cart!

We will have two 10' doors, and one 8' door. DH insisted on this arrangement. Is this unusual?

We have 3 doors, 9' wide each. I didn't look hard for a 18' wide single door, most are 16', but that could've swayed me back to a single big door. If you get the 9' wide singles and have trouble pulling in or backing out, you should consider taking mass transit.

As for the other reasons for one big door, I completely understand the benefits, but none of them applied to us.

We also made the garage extra wide and deep. 25' wide for the double bay area, and a hair under 25' deep. Our third garage bay is a stand alone 11' by 21'. 25' deep allows for a very large SUV and my garage cabinets/workbench to co-exist. 25' wide is pretty good for two sets of doors to open, but a wheelchair would be an issue on all but one side.

Now, if I can just get all the junk put away in the cabinets so you can find all three parking spots.

Whatever you do, please try to get more space inside the garage - period! We just got plans approved, & ours will be 25'8" x 29'10" - two single 9' wide doors + a man-door.
We grew weary of home shopping, finding a great home, then seeing that they put a 19' square pad as a garage, then put a 4-5 stairs up to the house inside one of the bays. Takes it down to a 1-car, unless you drive a Smart Car or Harley.
A garage is deadly cheap square footage. Then you have room for the 9' doors and plenty of storage, + room to walk around your cars without scratching them. Then you can actually (*gasp!*) open BOTH sides of one car - at the same time.
bdpeck - luv'd your opening comment. I liked the 3rd bay separate plans, but we put that money towards other things in the plan.

Good luck!