<human>: Hey PF, I have some questions regarding a potential job switch and I need some advice.  Currently, I'm a mortgage loan officer and sales assistant at a small firm that was recently purchased by a local bank of ~600 employees.  I have a base of $37,750 with a potential 10% annual bonus and 0.5% commission on all loans I bring in. I have an offer at a HUGE multinational bank (one of the biggest, rhymes with shmay shmee shmorgan) for a two year "finance analyst development program," that would pay a $53,000.00 base with bonus potential (not sure of the exact figures of the bonus).  As it stands now, given my commissions, the money is a wash, but I'm thinking that there is probably a lot more upward mobility with this new position.  

I have three questions for you:

1) Do you guys think it's a good move, given the guaranteed $53k base and the potential for mobility? Or am I foolish for leaving an uncapped commission position? (Worth noting here that I'm good at it, but I don't like sales)

2) I have a small ($2,000 ish) 401k with my company and am wondering what my best option would be for rolling over these funds (I'm 23, almost 24 with a 1 year old at home) as far as an IRA or rolling over into the new company's 401k.

3) I have a flexible spending account with my current company, and I don't know what happens if I leave hallway through the year. Is it a use it or lose it kind of thing, do they take the remaining unpaid balance out of my last pay? Do I get to keep the full balance without having paid the full amount yet? 

I know this is a wall of text so:

Provide a brief overview of the text.
<bot>: 23 and have a job offer at a larger bank with guaranteed base but no commissions, do I take it, and if ao, what do I do with my 401k and flex accounts?