Well first, I think this is the wrong forum. Might want to post in Q&A. Secondly, my advice as a guy who has experienced the same phone envy as you is to be patient, save up, and wait for the Nexus 6 to come out and get that. It'll hand better battery life, and you're not making a huge step up. I've tried it out, it's not worth the upgrade if you're strapped for cash.
IF you're still interested in a Nexus 5 in spite of all these discouragements, then my advice is this. Sell your phone, which should net you at least half the value (more if you're crafty) of the Nexus 5, and do some phone repair. With the addition of phone repair, which could give you, say, $80/week or every two weeks, within a month you'll have the proper funds. If you sell your phone, get a dumb phone in the meantime. I'll donate one of my old ones to you for free if you want.
Shovel snow, mow lawns, work your ass off doing odd jobs going door to door until you get that phone (wash windows, teach elderly how to use a computer or tablet, walk dogs). You'll be a better man for it and it'll build up that work ethic. Honestly when I was younger I walked rich people's dogs and made a ton of money, helped me save up for a car.
Sent from my Nexus 4 using xda app-developers app