2003 Dodge Stratus transmission issues

I have a 2003 dodge stratus- automatic transmission. My engine light has come on and the car seems like it is loosing pressr in take-offs. Coleman-taylor did a diagnostic and came up with codes P700 and P090 (i think). The service manager told me that I need a new torque converter and that they are going to have to tear the transmission down to see whats going on inside because there is something inside that is tearing up the converter. He mentioned that the "module" and the sensor may be causing the problem. The toatl cost fot this is $1,923.89 . This all seems kinda steep to me and seems like im being taken for a ride because I am female and it was obvious I was clueless about transmissions. Please help. Any advice?