Man Maths = buy a 1987 JCB 3CX Sitemaster

With rather a lot of work needed around the family home and ajoining patch of land a case of Man Maths broke out and resulted in the purchase of a 1987 JCB 3CX Sitemaster ('Black Cab') Backhoe with Extradig backactor and a Q-Fit quit change system on the front loader.
The 'maths' was that the purchase price of the JCB delivered came to less than hiring a similar (granted much newer) machine for 10 weeks. We have more than 10 weeks work for it lined up and further 'maths' deduced that we could recover the purchase price selling it when we are [cough] done [cough]