Decker on the cheap?
Evotech Himitsu - Data Processing 1, Firewall 2, Sleaze 5 (11000)
Attack Dongle 1 to 6 (3000 x rating x rating)
Device Modification - Add Module (500)
Cyberdeck Module - Program Carrier (900)
Minimum cost (with Attack Dongle 1) - 15400 nuyen
Device stats - A1, S5, D1, F2, plus one hardwired program of your choice (probably Virtual Machine). An absolute bargain!
Mid-range cost (with Attack Dongle 3) - 39400 nuyen
Device stats - A3, S5, D1, F2, plus one hardwired program of your choice. More effective than the only cyberdeck you can get for that amount of nuyen (the Radio Shack PCD-500).
Maximum cost (with Attack Dongle 6) - 120400 nuyen
Device stats - A6, S5, D1, F2, plus one hardwired program of your choice. You're probably better off buying a Little Hornet or C-K analyst and modding that, but still a passable option.
Note that with Virtual Machine, you can run two programs to boost your stats further. Decryption + Stealth can put you on par with some of the higher-end decks (though your Firewall and Data Processing remain horrible). A good, cheap system for an AR decker.
EDIT: The book says it's (Rating)2 x 3000 nuyen, which could either be rating x 2 or rating squared.
EDIT2: Those in the know are saying it is rating squared. Prices adjusted.