A friend bought 4 el cheapo 300kg electronic platform scales... and a few planks of wood.... = ghetto Corner scales
Work fine with a mini....
eg Ebay - can probably find cheaper on the "bargain" sites...
http://www.ebay.com.au/itm/NEW-300KGS-300-KG-ELECTRONIC-DIGITAL-COMPUTING-PRICE-WEIGHT-PLATFORM-TRADE-SCALE-/280616316065?pt=AU_Envelopes_Bags_Boxes&hash=item4156092ca1eg highest corner weights (with me in the race car) 240 front, 150 rear ( I don't have a light weight special

)
PS Handy Corner Weight Calculator and Spreadsheet here
http://robrobinette.com/corner_weight_calc.htm