The Aptera Forum
Co-CEO Chris Anthony has stated that they considered 3 seats but thought very few would want one. However with recent requests for one, he said they are reconsidering offering that as an option, but it would fit only with the smaller battery options.
They have stated they would not include attachments for child seats. Some states laws explicitly say that child seats and baby carriers are illegal in autocycles or on motorcycles.
2 seats were probably designed for larger people so they can actually fit in the car, but it would be greats to have option of folding down/removing the armrest so smaller people can carry a third person. also a child seat may fit in the back given child will be facing backward like they would in normal cars
Design it like a Maclaren F1. Place the driver in the middle and the passengers staggered on either side. This would also have the advantage of being market ubiquitous, removing the requirement to make separate interiors for LHD and RHD markets.
If you want a third seat. Buy a different vehicle !