What size engine is your Tipo?
The self adjuster should turn the cog to take up any slack. What condition are the brake cables in? Replacing them isn't a hard job, just fiddly and time consuming. Best thing is to take the drum off and have a look around inside. Remember an 'N' plate is about 10 years old and probably on original drums and possibly shoes! Check for a big lip on the inside of the drum. The self adjusters are fragile, fiddly things - wouldn't be suprised if its broken.