I just signed up for a membership with Costco wholesale club. This is really going to help me out as a Lyft driver. My car is supposed to run on Premium gas with the "Top Tier" designation. At the Costco gas station in New Britain, premium gas is currently $2.38/gal and regular is $2.17 (no mid-grade offered). Both prices are well below the state average and their gas has the Top Tier endorsement. Membership starts at $55/year. I think it will only take about a month to see a return on that investment. They also have great prices in motor oil and bottled water.