Free or cheap AV/Firewall/Internet Monitor Software for small Business server

[SolMiester]

Hi all, building a small business server for a friends company, will have around 7 pc running off it.
I would like some corporate AV firewall software that burn his pocket & an internet proxy service would be grand too just to protect against dodgy software downloads etc.

Any suggestions guys and girls?

 

[SolMiester]

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