Uum it depends on what the financial calculator is supposed to do.
I know that TI's are very broad and powerful calculators, and probably are capable of doing everything you want. But it is possible that they lack a few buttons that calculate some special financial stuff, but if you know what the buttons do (which is good to know

) you can just do the calculations. Also, you can write a BASIC script that does that calculation for you. (so add programs/apps to it)
I can help with some basic, BASIC scripts, if you tell me what they need to do, etc.
EDIT: I just googled the financial calculator, and they pretty-much are simple TI's
http://www.amazon.com/Texas-Instruments ... B00000JZKBSo by what I can tell, the TI-84/83 has all these functions. But they may be hidden away a bit better

like ncr and npr are under a submenu. (On my TI-84, they are under the MATH button and then the PRB tab. So first column, 3rd button and then press right 3 times.)
If you have any more questions, then please ask

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