Without knowing where the question fits best, we're trying here.
Considering the most sensible construction for an electric wheelchair storage with "extra space". The thoughts are along the lines of a log cabin, like the picture/link but extended by about 1.5m so that the storage becomes the extended space. http://www.solbostugan.com/sv/produkter/solbostugan/-solbo-149--pid102.htm
It would then have space for a narrow sectional overhead door (such as those with 150 cm width) with remote control, which would be quite convenient. The question is just how to handle the part of the floor that ends up outside the door if you know what I mean? Also, I don't want moisture damage to the floor...
The alternative is obviously a regular door of a wider model, but door openers with remote control for such doors are not exactly cheap, and sectional overhead doors have advantages like avoiding thresholds, width, etc.