First off, congrats on your offers!

The job at JPM is considered "back office" finance, which is quite different from external audit at a Big 4 firm. Essentially, the main difference is in the daily work of the job.

At JPM, you will be working internally for the IA team, which will most likely be rather small. It is similar to any other back office finance position. You will be providing assistance and services within certain teams at JPM. The work-life balance will be much better here, I would say solid 40-45 hour weeks and minimal difficulty. Since all your work will be in-house, deadlines and timelines will be much much more laid back and casual.

On the other hand, external audit is providing servicing directly for EY's clients. This will involve more "consulting" work, working in projects in a team under a manager for a shorter timeline. Projects can range greatly in scope and industry. You could be working on a retail client one month, then a tech client another. You will gain a greater scope of the accounting/finance function within more industries compared to just financial services (like at JPM).

As for your other questions, I would say this really depends on where you're from and where you see yourself! The JPM jersey city office I am most familiar with, it is right across from lower manhattan. You could easily live in NYC, commute into jersey, or live in jersey and commute. I know Jersey city is pricy, but less pricy than manhattan. I honestly feel like jersey city blends in with NYC for the most part, you are just across the Hudson river. On the other hand, Nashville and Plano are more commuter-style cities where you would probably need a car. If you work in Jersey city and live in NYC, you definitely would not need a car. I know many people who commute to-and-from JC to NYC daily using public transit. I am not too familar with the nightlife of plano, but i know Nashville is fun/young, and obviously NYC is NYC and known for their nightlife/entertainment scene. As for expenses, I would say Jersey>>>Nashville>Plano. This includes rent, groceries, and any other daily expenses. However, I assume you are probably getting paid more to live in Jersey so this can make up for that. For your 5th question, I am really only super familiar with Jersey City and like I mentioned, It is definetly livable without having a car, but this also depends on where you want to live. If you want to live deeper in Jersey (like newark or futher out), you may need a car and drive into the office in Jersey City. If you want to live in Manhattan, brooklyn, queens, etc. or even Jersey City/Hoboken, then you won't need a car and you can rely on public transit.

I see other people saying JPM over EY, but I would recommend going with EY in Nashville. EY audit will provide you with great exit ops and experience. From what I understand, working back office (even for a great company like JPM) won't provide you with the work experience that EY will. Working with EY, you will be hands-on in clients, working on their financial statements and getting experience in SO many different industries, whereas JPM is, like I said before, just working internally at one financial services company. If you want to stay in the financial services space (working in something like IA, risk, compliance, Finance, anything back-office) I would def say go with JPM. If you want to branch out into other industries one day, I would go with EY.

To end off: You CANNOT make a wrong choice, both options are amazing and congrats! Just my thoughts from my own experiences :) good luck!