I got a question about whether it was better to have a 5x6m parking garage or a 6×6 one. Well, it depends on your budget, of course. It also comes down to how comfortable you want your parking to be and if you want additional storage space.
One (5,7m) door is expensive, and when it breaks down, you won’t be able to get in (easily) any more. One 3,5m door requires careful parking but is the cheapest option. Personally, I’d go for two 2.6m wide doors, so both cars can be parked comfortably. It also allows for a 20x20cm centre support beam, which can make your construction lighter and more economical.
If you want more storage space, you can make it 6m deep instead of 5m, but this comes at an extra cost. It doesn’t look like much, but it is an additional 2m of wall and 6m² of floor and (flat) roof.