Starting my 1st build. Any tips ?

[Buckaroobonsai]

I would say, DON'T DO IT, but it sounds like it's too late! Once you start playing with AR's it's easy to go crazy. I bet in a month's time, you'll have a box full of spare parts, almost enough to build a whole new one! Cut up the credit cards now, and thank me later! Ok, since you've already joined the "dark side", here's some truly useful advice:

Buying local is great for technical support, online and YouTube are great too. Spend time viewing all the different builds on forums as it's easier to know what you want, when you know what's actually out there. Pick up a spare parts kit, as springs and detents have a way of disappearing. Prepare a good work space with proper lighting and have a few trays around to hold parts while you work. Get a decent vise that's padded along with a block kit as it will come in handy for just about any job. Last but not least, take your time. Rushing only leads to screwing something up that will require even more time to fix it!