2009 Hyundai Sonata fuel injectors

My dealer says I should have their fuel injection service done shortly at the tune of 150.00. The car runs wonderfully. I use 85 octane guel and our elevation is 7000 ft above sea level. Is theere something I can do myself so that I won't be spending 150.00 every 15,000 miles. I'm 79 years old and can't afford to waste money now. Do the vaerage parts house have something that wouold clean these injector tips? Thanks