Form 12 - Maximum NET non-paye income?

I work in a full-time paye job. Since last year I've also been doing some part-time non-paye work.

I got in touch with revenue about getting this extra money taxed and they added my estimated net income to my tax credits form. When I do my tax return for 2009 this year that should be fine as my net income was less than 2k.

However, I have the opportunity this year to make probably around 5k. I've read threads on here and boards.ie that say the maximum net amount you can make is roughly 3k. Does anyone have a definite source on that from the revenue site.

I found a link on the revenue site which, as far as I can tell anyway, only mentions a max GROSS income of 50k. Unfortunately I can't post urls as I haven't made 15 posts. But it's a pdf called 42-04-13.pdf

Also does anyone know what allowable expenses I can write off against the gross amount to get my net profit. The work I'm doing is wedding videography so I've been presuming that things like cameras, editing software and general equipment would be allowable expenses?

Thanks for any light anyone can shed on this.

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Gross income of more than €50,000 (Before expenses) or net taxable income of €3,174 or more brings you under self assessment rules.

Perfect. Thanks for that.