Your better off just keeping your eyes open on ebay for a bargain diesel around 5 to 600, Although if you only using it a couple of times a month then a petrol will be ok, there always coming on ebay around 500, 11/13 horse power hondas, make sure it's an interpump pump, annovi reverbi or better still cat, 15 litres per minute at 200 bar (3000psi)