No way of avoiding a big hit because you will be buying in the summer when demand for this type of vehicle is highest and selling in the winter when demand is lowest. If buying diesel, avoid anything with a diesel particulate filter. A pre-2006 Galaxy 1.9TDCI is the most common, but any 7 seater for £5k is likely to be well used. You could get a newer, later model from Addison Lee from around £7,000, but that will have a DPF, but will also have the advantage of being automatic.