Is this bad r ok to do?

ok so i got a civic for 200 dollars n its parked up at my girl friend house n when i was walkin home i seen 1 that looked liked mines so i knocked on door n the lady say she is sellin the car for 350 and i told some1 about it n they put 100 on it so when i ask my friend whats going on with the car he said he ran into problems so he went back to the lady house n took back his 100 dollars now i have the money for it i want to buy it n sell it for 1700 the car is mint it just over heats n thats a easy job to fix so what should i do