Doing it yourself?
CSW or Hard Top? (wheel arches inside/or not offer various opportunities).
There's a few tips on my thread about the previous build I had - sleeping platform made of lightweight ply with pine bracing underneath, resting on storage boxes which slide out/lift out. Advantage is it all lifts out when not needed, is strong enough for two people, and the sections when lifted out form seating and a table.
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