It really depends on the bunny and the home. Some bunnies are much more apt to get into trouble — sneak behind appliances and places you never thought of, while others are more chill and stick to a particular exploration path. My first bunny was a free roaming bunny and he did great. In Jack’s younger years, I couldn’t fully trust him as he would be really good while I was there, but if I was gone for more than a few hours, I would find him up on the couch – either peeing or chewing on the couch cushions. However, a few years later, he had mellowed out and if I wasn’t dealing with other bunnies too, I think he would have been fine.
In the last few years, I would have both he and Vivian (and when Rucy was alive) fully free roaming 24/7 if we didn’t have a cat that I don’t trust alone with them. Right now they have the bunny room during the day, and they are allowed to free roam from about 11pm until about 8am. We close off our bedroom and hallway and allow the cat to be in there with us at night separated away from the rest of the house and the bunnies. When Jack was not ill, he and Vivian would play alot at night and especially around 5am — you could hear them running around like crazy. (And of course, they just chilled then all day as if they were some big lazy lumps — when in fact they just partied all night. LOL).
As long as you have all your bases covered as far as house proofing (OH, and keep the toilet seat down – my bunny Rucy jumped in the toilet one time because she liked to sit on the toilet seat. She was able to jump right out, but I would be afraid if someone’s bunny couldn’t).
Sometimes a more curious active bunny can get into trouble while you are gone and so you just want to be really aware of all of the trouble-making opportunities and then do what you can to prevent them. You can also block off certain rooms that you don’t want to take chances on just yet.