Hello!
I rather see a problem with your annual budget than with the purchase price. What if "they" decide to make you install a mode-S-transponder (as "they" already did in other parts of the world that are closing in around you)? There goes your annual budget at once. Or an examiner finds a corroded crankshaft during the next annual inspection? There go two annual budgets. And so on.
Having owned 1/3 shares in two aeroplanes over the years I really have no illusions any more regarding owning vs. hiring. Always expect the unexpected and then triple the associated cost...
I don't know much about permit-to-fly aeroplanes in the UK, but any type on a C of A anywhere in Europe is not going to fly a single minute on basis of a 5000 Pound/Euro budget.
Happy landings,
max