Rentius, you did just great. If you want to follow a conversation, click on "view conversation" under my post, and then the messages with me will be all together.
Most people like to use a van with a powerchair--a minivan or SUV is most often used, with a ramp installed along with a dropped floor. This is expensive if new, but there are normally lots of used converted vans for sale. You really will need a big power wheelchair, with tilt, elevated legs and reclining back. We live in these chairs, Rentius, and can develop pressure sores if the chair isn't the right size and doesn't have a good cushion. A sedan would supply room only for a collapsible manual chair.
I can tell you that the doorways in a house should be bigger than 30 inches wide. I don't know metric, but as close as 36 inches would be the best width, and with nothing blocking a turn while going through a doorway. Try to get a bedroom and bathroom on the main floor, and if you are able, a shower room is best.