When i turn it on the light goes green then it goes yellow and off

Are you sure it doesn't turn yellow then blink red?

Yellow light and off: Power supply and board might have been overheated, pulling the gpu and cpu off the main board.

Red blinking light, board is overheated and the gpu and cpu has pulled from the board.

Both are easy fixes for a professional and should cost you no more then 100 for power supply and fix or 50 for the fix. That's what I charge. Anyone who charges more is ripping you off. It is even better if you can try this yourself, but reheating the board yourself is dangerous if is done wrong and can leave you with an incapacitated Playstation.