I don't know how a pinz would do on a towbar. If you're nervous about it you could either use an equipment trailer, or stick a reciever hitch on your 109 and pull a properly sized car trailer. The car trailer option would surely be lighter and might slow you down a little less on the hills. Plus you'd have brakes on at least one of the trailer axles... Maybe both.
If you do go with the towbar option, you might be able to borrow one of mine.
If you do go with the towbar option, you might be able to borrow one of mine.