My folks have had a rat issue for some time at their place. They consistently get into the roof and cause havoc up there. He won't bait them as when they die they have a habit of burrowing into the roof insulation to die thus making it a mission to find them. He has tried everything to try and block their passage into the roof, from expanda foam to wood. They still get through, with the latest and hardest to believe (till I saw the hole) they chewed through the lead flashing on the roof to get in. Last option is a cat but they are not overly keen on that option (note: the neighbours have chickens and this is where the majority of their issues stem from).
Garry - don't get me wrong I'm not into cruelty, I just didn't realise until the last issue I had that the bait takes so long to take effect. Snap traps will have to be the solution.
we had ferrets for years and were awesome pets. they are pretty toilet trained (not fully tho) and yeah a bit on the nose. kept outdoors under cover and taken indoors at times is best. they sleep a lot and when awake its like party time. good for roaches but not so sure about rats.
I would advise against ferreting unless the ferrets are experienced. Inexperienced ferrets are inefficient killers, they take too long to kill their prey so this results in a thrashing rat that's fighting for its life. Rats have very sharp teeth and they can do damage.
And, yes, ferrets do have that musky scent but it's not that bad unless you're negligent in cleaning them/their environment.