I'm a freelance accountant, for 3 years 70% of my income has come from 1 company, should I just work for them?

I'm 26 now, and I started working for this company 3 years ago. I get other companies to hire me for my services, but many times in these last 3 years, that 1 company has been my sole source of income.
I don't even sign the visitors log at the lobby, most of the time I just get in directly to the finance department.
I celebrate other people's birthdays in the company, and they've even celebrated my birthday in the office.
I get along with everyone in the department, and everyone jokes all the time practically being another employee. They have seriously considered giving my own cubicle even if I'm not really an employee just because I'm there most of the day. They have seriously offered me a position there several times, but I like the idea of being my own boss even though I pretty much just work for the same people all the time. Sometimes I do worry what would happen if they decide to hire a full time accountant to do my specific job.

Should I jsut take a job with them?

You can always be your own boss. If you've got an opportunity to go work at that company full time, why not give it a shot?

You'll get benefits. You'll have more job security. And it sounds like you like the people there, so you'll have a team that you know and are comfortable with.

Nothing wrong w/ that... In fact, many people look for such a job where they can be happy and productive.

If it doesn't work out and you get itchy feet in a few years, you can always return to self employment, wiht your resume enhanced by the experience.

Good luck!