JCHCG on Nostr: My accountant just sent me text explaining to me how she has this client who has ...

My accountant just sent me text explaining to me how she has this client who has bought bitcoin through an investor, but this investor has now retired.
The investor gave his client all the information (password, login info) needed to retrieve his Bitcoin but he doesn’t know how.
My accountant has asked me to help retrieve it.
I’m wondering if I Should be charging a percentage of whatever he has or a flat fee? What would you guys do?
#asknostr