My first accounting job was for a small accounting firm (owner wasn't a CPA) – when I started, it was me, the owner, and a part-time college kid; later on it was just me and the owner. I worked there for a year, and then that experience helped me get the next job, and those two jobs helped me land a 3rd job which I'll be starting next month.
My thoughts on the opportunity are that you'll learn a much larger variety of things working in a small CPA firm than you will in a large one. Like you said, you'd be doing auditing and taxes, probably both from the bottom up. In Big 4, you do one or the other, and see just 1 piece of each, instead of doing all of all of it. So, much more varied learning. This can somewhat make you a “jack of all trades, master of none”, but we've gotta get our feet wet somewhere! Before working in the “real world”, all that we know is academic, so I think that a job like this is great to start out so that you can see what it's all like.
On the flip side, sometimes the reason someone has a small firm is because they lack something necessary to grow it, and in my case that was the situation with my employer. It ended up turning into a bad employer/employee relationship because he's not a good manager, and I came to understand why he'd never had any long-term employees.
Also, the pay was low – I know the offer you received seems appalling to you at the moment, so I'll throw out my pay rate just for comparison: I was offered the job at $8/hr. And no, this wasn't in the 80's when that was real money – this was in 2012, when minimum wage was $7.25/hr. In fairness, we're in a really low COL area where the wages are significantly lower than the national average, but still, $0.75 above minimum wage was pitiful, and I wonder now why I wasn't insulted enough to tell him off. He gave me a $1 raise (12.5%) a few months later, so when I left that job I was making $9/hr. (The ironic thing is that even before my raise, he'd talk about his wife's job and how she was paid so little it was barely worth having her work. She was a medical receptionist, so I'm sure was making at least $8/hr if not more, so to whine that his receptionist wife without a degree wasn't making enough and then pay me, his accountant with a degree, the same or less was in very poor taste!) However, even though the pay wasn't good, the experience was invaluable. I saw things start-to-finish and learned a lot. Another consideration is that being paid hourly means that you'll likely get a lot of overtime pay during busy season, so you may end up making more than your friends who landed jobs with salaries.
P. S. A prior poster mentioned that her small-time boss had family coming in and out all day, a messy house, etc., so just wanted to say my situation wasn't like that. I met my boss's wife and his sons about one time each, except the son who worked in his office for a bit, but it was all very professional.
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