A Competitive Deck For Beginners

So there's this friend of mine that decided she likes yugioh, and so she bought some cards, and got some cards from other people. I'd like to make her a competitive deck, or at least semi-competitive, and it would be cool if it didn't cost a lot either. I need something that basically runs on autopilot, because, well... she's kind of a noob lol, just saying. She learns fast, but yeah. Anyway, I know I can't get her a lightsworn deck or something like that without investing a good amount of money, but she isn't going to go to regionals or anything like that, so a tier 2 deck or an original deck would work fine. Problem is, nothing comes to mind atm. Any suggestions? I know there's some awesome
deck builders here

Lol if you friend dont want to waste a lot of money in cards, the best choice for a cheap competitive deck is The Machina Gadget. She only need to buy the 3 machina mayhems structure, then all the rest of the cards can be found in comons ( except for mirror force of course ) that will be m,y 1st suggesgtion. But if she dont like it , then we can go to other conpetitive cheap decks but those decks dont really work in autopilot, she will need some experience to handle them. those decks can be Frog decks ( the des frog version ), Six Sams ( almost all sams can be find in comons version expept the bigest ones ) and thats all that comes to my mind right now.

how about gladiator beast, they are cheap, they are mostly commons, or monarchs, you only need to spend money on battle faders,

Thanks for the suggestions guys! I think I'm going to go with Machina Gadgets, and Gladiator Beasts as a 2nd choice. Glads take a bit of experieen e to know which one to tag out for. What do you think about this decklist for machina gadgets?:
       Extra:
Chimeratech fortress dragon x2
       Monsters: (18)
Machina fortress x3
Cyber dragon x2
Red gadget x2
Green gadget x2
Yellow gadget x2
Machina gearframe x3
Machina peacekeeper
Scrap recycler
Cyber valley x2
       Spells: (13)
Smashing ground x3
Fissure x3
Book of moon x2
Lightning vortex
Limiter removal
Heavy storm
Mystical space typhoon
Brain control
       Traps: (9)
Dimensional prison x3
Mirror force
Bottomless trap hole x2
Torrential tribute
Royal oppression x2
       Other cards I may add in
Machina peacekeeper
Pot of avarice
Giant trunade
Overload fusion
Future fusion
Solemn judgement
Dust tornado
CoTH

cyber valley is not worth to put in the deck
O.O there is no limiter removal
O.O 2x Royal Opression with 3x Machina Fortress

the cheapest is machina.. just like scorp said, but 3 structure machina mayhem.. Maybe just need future fusion, jinzo + returner, chimeratech (both).. and all the staples card (mirror force, bottomless) but besides you get all the monster you need, you also get pretty decent trap and spell.. Solidarity, D-Prison, Trunade, and I can't remember others.. My opinion, don't run machina.. Because everyone in regional run System Down on side deck.. XD

Tino The Sinner wrote:

cyber valley is not worth to put in the deck
O.O there is no limiter removal
O.O 2x Royal Opression with 3x Machina Fortress

okay, -2 royal oppression and -2 cyber valley. What should I replace them with? Haha, and "limiter overload" is limiter removal, I'm not sure why I wrote overload... That's some random trap that let's you summon speed warrior o_O
fouzman: thx for the advice, i'll keep some of those in mind. Returner and jinzo are suited to their own deck I think though. Like I said, this is for my friend, and she probably won't be going to tourneys and stuff, but I want her to have more of a chance to beat me and my friends without spending a lot of money. Besides, saying not to use machines because of system down is like saying don't run infernities because of consecrated light. Sometimes you just have to take the risk