I just bought a 2007 Dodge Caliber SXT 2.0L that was sitting for quite some time and the previous owner says he never had any transmission or motor issues with it.

When i purchased it the issues i was aware of were:

needing rear brakes
needing new battery

i replaced the battery the same day i purchased the car. However when driving it i noticed it not taking off properly. I could floor it and it'd still take forever just to get up to 10mph. Once it was going it was fine, but it had a very slow take off.

I had it diagnosed while getting the battery replaced and was told i had a random misfire and could be fixed with a simple tune up. I got a tune up and while it fixed my misfire issue, it did not take the vehicle out of limp mode.

I did more research and learned about the transmissions not being very good in this vehicle. I was now faced with code p0730 i believe (maybe wrong code, i know the code read Incorrect Gear Ratio)

The fixes seem to be as follow;
New transmission fluid
New solenoid
or new transmission

I took it to a transmission shop and he replaced my input sensor and added new fluid. THAT did not take me out of limp mode either.

I am starting to accept its the transmission, but i fear that ill dump all my cash into the transmission just to find it needs a new solenoid.

The check engine light is no longer on since the sensor replacement, and the shop says i just need go get the car reflashed and itll be out of limp.

Is this true? im reading that reflashing doesnt fix limp mode but am also reading that it does.

My caliber also has 130k miles and the fluid was changed at 100k (so the owner says)

what are my courses of action here?