Mine is a group aircraft, and we pay a dry rate - thus you pay for whichever fuel you put in. (The biggest argument against charging a dry rate - the temptation to over-lean - doesn't apply to our Rotax 914 because it doesn't have a mixture control.)
Algirdas mentions using fuel from a high-turnover station. He suggests that the constant flow may reduce dirt building up in the nozzles, and that is probably true. But the constant flow does not help the filters! We used to use fuel from a fairly quiet garage just outside the airfield, and found we had to change the filters every few hours. Checking the state of the filters was a vital part of the pre-flight, and the first action for a rough-running engine was to turn on the boost pump which bypassed the main filter and used a backup filter instead. We never put two and two together until the garage closed and we were forced to use one further away... and then our fuel filter problems went away.
FFF
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