If you use used oil then you will have to heat to 70c and leave for a week or two for the water to drop out the longer the better then filter down to 1 mic and change you engine oil every 3000 miles and in the cold weather mix petrol around 10% to stop it going off best bet is to twin tank if you can.
I run Bio and have done in many cars for over 4 years and 30,000 miles with no issues just change the odd fuel filter.