Coolant Leaking problems of the 2012 Chevrolet Sonic

12/23/16, I purchased a 2012 Chevrolet Sonic. 4/6/17, I was at a traffic light when smoke come in the vents from the hood of the car. I called onstar & to run a diagnostic. The diagnostic didn't return any information & I contacted the dealer & took the vehicle for service on 4/9/17. I was told the thermostat housing was leaking and caused the smoking. The coolant system was flushed & filled & a gm oil, lube, filter change was done. The vehicle was ready for pick on 4/19/17. A few weeks later the car was smoking again. I called the dealer, I was told it was probably just fluid on the engine. The car continued to smoke periodically. 6/7/17, there was a large pool of oil under the car, I took the car to a local shop. They said that the oil had been overfilled & that it blew a seal. I called the dealer, I was told they did not overfill the oil & made another service appointment. I was told again there was a problem with the coolant system & the oil & that was the reason for the smoking. Repairs completed 7/10/17. 9/27/17, while driving the check engine light came on, so I called onstar for a diagnostic & they gave me an error code p0299. They told me that it was an airflow problem. I called the dealer & asked for the service manager & gave her the error code. She said there was a problem with the turbo & that I needed to bring the vehicle in. I took the car to them 10/3/17. 10/4/17, the service department called me & told me that the turbo on the car was bad. The repairs were completed on 10/12/17. 10/13/17 the car overheated. The vehicle was leaking coolant in two places. I took it to a different dealer & they said the t-joint in the coolant system was leaking. The repairs were completed on 10/18/17. 11/3/17 an email from on-star said there was an engine problem. I contacted on-star for a diagnostic & they said something is wrong with the coolant system.