Deployment in the field is likely to be key to the practicality of personal air vehicles and although I've always preferred two-dimensional constructions over stacked units of whichever kind, I'll make an exception for this arrangement, which as ever has been drawn from the back-catalogue.
The tic-tac-toe arrangement of octocopters has long been a go-to choice for projects around the world focussing on rough-and-ready construction of personal air vehicles.
It can be used to advantage here, however, by its division into identical 'bogies' bearing four motors each and with a layout like a dog-bone.
Once eVTOLs are scaled to include the human form, they need to be adapted to all of those other appurtenances of life that is equally so: including cars, ceilings and doors.
It is altogether too easy for home-builders to make boats or aeroplanes which require disassembly of either the craft or workshop on completion in order to extricate them, and vehicles of this kind are no exception.
And afterwards your talking roof-racks or trailers to reassemble or deploy them in use, and as such we need to start as we mean to continue.
We're likely to work to around two-thirds scale for a proof-of-concept, in which case the centre-body seen in the diagram is 14" square, the propellers remain 22" diameter and the airframe (discounting the swept area of the propellers) is 48".
Thus even at this stage it is clear that the assembly will only slide into the rear of your hatchback should the modules remain separated for transport.
For you learn nothing about eVTOLs until you've had to tote them here and there, and I've friends and colleagues who've had to trailer them over half the width of the USA.
