My 2012 RV0-12 has 380 hours, half from builder, half from me. Recently the plane has become increasingly difficult to start, and now- it won't start. After several tries, after checking one of the carbs for fuel in the bowl, I purchased some starting fluid to see whether the issue is linked to the carbs. spraying a good deal of starting into each carb air filter, when I turned the engine over with full battery power, not a hint of starting. My next step is to pull a spark plug lead and take an new plug, hook it to the lead, hold it on the engine and have someone turn the engine over to look for a spark. Does anyone have better, more experienced opinions on what the sequence should be to track down the problem? The builder is long gone. Mark