There were 28 cattery pens and an office building to get rid of.   We really didn't want to have to pay to have this removed, so we put an advert on Facebook, and were inundated with calls.  We sold the lot for 2.5k and after 3 days of removing the roof structure (didn't want to risk people falling through it), the buyers came and removed it.  They left a complete mess, but I spent a further three days putting the remnants in one 4 yard plasterboard skip and 2 * 10 yard skips.  This meant we were still up 1.5k, so not a bad result.

Pictures of the site before clearance and afterwards.

The next task is to hire an excavator and break up the masses of concrete slab.  Hoping that it is not reinforced so that I can hire a crusher and recycle the waste into hardcore.