No one should let their dog roam free, period. Particularly since I think you wrote that your hounds are intact, Funk is gonna go looking for females in season. You want your dog fathering unwanted puppies down the road somewhere?
Sorry for the lecture, but I had to say something.
Some people have success with invisible fences, others say a determined basset will ignore the fence "zap" if they are chasing a rabbit or other animal.
My 2 hounds live indoors and have a decent size fenced backyard. Free access in and out via doggy door.