el miguel42
get yourself a copy of "Light Aviation" January 2008 , better still join the LAA (PFA )
http://www.laa.uk.com/
Inside this months magazine is a very informative article on all the considerations and costs involved with buying an aircraft. It will probably answer at least 90 per cent of your questions.
Your original idea of a Shadow (group A ) is a sensible choice of aircraft for what you want.