you can pack a surprising amount of stuff between the front of the passenger seat and the bulkhead. i can't recall the last time i actually needed a spare tire (okay - it might be a good idea for a long roadtrip, but then you need the jack and lug wrench too ...) But these cars hold A LOT.
when i attended the Portland, OR Parade we drove from San Diego straight through - with a (small) floor jack and complete detailing supplies for the conccours, track stuff for the autocross (2 helmets, various accessories...) and clothes for 2 for a week.
soft-sided luggage is a must.
(and i have it on good authority that they sell camp chairs in San Francisco too, and for $8 total investment, they could be left there... but that's irrelevant of course

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