Bickering. Endless bickering about what funds should be spent on, if subs should be raised and suspicious members questioning your every payment.
Inconvenience of having to deposit cash. If you work full time it can be a burden.
You must be well organised and keep on top of things. Never accept cash without making a note of it - you will forget who gave it to you and what it was for.
It can look very good on your cv, if that is important to you.
If you are a worrier, get over anxious or stressed, turn the post down. If you enjoy a challenge and have good people skills, you'll enjoy doing it.
Consider realistically how much time it is going to take up, and if you have the time to deal with it.
If it's a large club with weekly meetings it will be far more demanding than a small club with quarterly meetings, obviously.
If you have a particular drum to bang within your club, turn it down. The conflict will be too great.
Look at the other committee members - is there anybody you have trouble dealing with? Remember you will be accountable so if you are a timid sort of person, don't do it.
It's impossible to predict how involved it will be without knowing the nature and size of the club, but I hope I've given you things to think about.