Bought my RAA Gazelle in 2002 for $28k. Did 500 hours and spent $0 on it in parts, bar oil and filters; maintainted it myself under RA-Aus regs. Sold it 2 years later for $45k. Built a 4 seat Jabiru for $76k. Out of pocket $59k. Have done 400 hours in 2 years.
Cost to hire, $120,000 over 4 years for those hours.
Cost to run, maintain & park (wet):
Gazelle - $12k.
Jab - $13k.
Approximate cost per hour $30 including engine allowance.
Sell now for $90k approx (could probably do better)
Profit when sold + $4000.
Therefore for every hour of flying I made $4.40.
This didn't include driving to the airport, maps, headsets and airways charges.
I hear you say, "but you built the aircraft, factor that in." Ok I will:
Add $18,000.
Therefore, hourly cost of owning and running = $15.50.