I believe I am right in saying that under current JAR FCL rules the following applies to adding new type ratings to your licence:
The minimum required flying hours is:
Single Engined Single Pilot - 5 hrs.
Multi-Engined Single Pilot - 8 hrs.
Multi-Engined Multi Pilot - 10 hrs.
This type rating training has to be carried out an an approved organisation with either an FTO or TRTO approval issued by the 'suits'.
The course can be tailored to meet the individual requirements however at present the 'suits' say that the JAR is the minimum they would expect to see on the LST (Licence Skills Test - new version of the 1179) form and unless you had a pre-arranged deal with the 'suits' to do less than the minimum, the 'faces' at the front desk would probably refuse to issue the type rating.