It appears the best bet is to decide what space you’re willing to devote entirely to your rabbit’s permanent enclosure, and then you can rabbit proof/put gates up against any sections you do not want your rabbit wandering around when you allow for free-roam time. At the minimum though, the space you dedicate for him does need to have a rug and, anticipating little room/clutter/not being able to rabbit-proof the entire space, be spacious enough to facilitate exercise over several hours of restriction time. Use of vertical space would be really helpful, so you can consider doing a more complex build with grid cages.
Here are some thoughts around that (please note this directs to a rabbit forum which is not exclusive to pet rabbit-keeping): https://www.rabbitsonline.net/threads/need-help-deciding-on-which-nic-cube-set-to-get-zip-ties-etc.102559/post-1181862
The answers provided in this discussion are for general guideline purposes only. The information is not intended to diagnose or treat your pet. Seek the advice of your veterinarian or a qualified behaviorist.