MakD
There is some very good advice in these last three pages. Forget the posts on cars any idiot can drive infact any idiot can fly but not everyone can operate an Aircraft safely. The 135 being a twin and having an advanced cockpit would give a workload that an inexperienced pilot would just not be able to cope with, remember flying the aircraft is the easy bit its the other bits that are the problem and until you can fly the aircraft as if second nature the more work load there is.
As has been said try to find someone that will give you some time on a Gazelle or similar, it will give you adequate power and is a wonderfully simple aircraft to operate but like all they can be a handfull.
Why a 135 anyway? the main operators in the Uk are Police and without being ex military you have little chance.
John