
If you do not want one for working, will you be prepared to find him some 'work' anyway, because you may not want to work... but the dog WILL and you cannot change that, though sometimes you can redirect it into appropriate versions of the work behaviour.
Honestly, I would say look again at the other terriers available, and aim for a show type that is a long way removed from the working version.
Terriers ARE hard work - they are stubborn, fiesty, fiery, they don't back down, if something is scary they take it head on and give it what for, they are sharp, reactive and like to bark. That isn't me insulting them, if they weren't all these things they wouldnt BE terriers - there is little point to a working terrier if it backs down, runs off, stays silent or quits. These traits are tempered somewhat in the show types, but they are the things working breeders will select FOR in a patterdale, and very very few patterdales currently will be more than one, maybe two generations away from purely working stock.
They NEED a job and they NEED a lot of exercise and training.
Patterdales are known as the psychopaths of the working terriers, and on the whole NOT suited to the average pet dogs lifestyle. For some reason they seem to have become quite popular, probably due to their size , but a LOT hit the rescues because their owners cannot cope, and a LOT get put down quite young for the same reasons. They are a VERY unforgiving breed if you make an error.
I would say; if you still want one after reading that, find someone who WORKS their dogs and go and see them WORK, and then think, can you handle that in your home and daily life.