@hazyj Personally I would always keep them on a leash. They have recall right up to the point when they see “prey” and then they are gone. Much like leaving them uncrated, it works until it doesn’t and then the consequences can be death, so to me it is never worth the risk.
Two mile walks twice a day would be fine if you could do it. I would not get a basenji if I did not have the time or capability to walk them enough. Sure they can survive but it doesn’t fulfill their natural desires and needs. I use extension leashes so for the 3-5 miles we do, they do about 6-7 lol. Although it takes time and concentration to use them safely.
Most of the people who come on here with problems and looking for advice, generally can be helped just by increasing the walks. Even taking them to the same park gets boring for a basenji, unless maybe it’s a dog park but they have their own problems.
From my own experience, during winter I walk them as much as possible but they are more stressed, have more problems with behavior etc. in the summer with 4-5 walks a day including one good two mile walk, they just want to come home, sleep and then get back out there. A tired basenji is a happy, good, well behaved basenji. In the wild dogs migrate as a pack, the more you emulate that, the better it is for the dogs health and well-being.
The walks are the key to everything. The reason I keep them is intelligence, they will keep you on your toes constantly and will outwit you. To keep a basenji you must be half as smart as the dog lol.