I am a single woman with no dependents. I would like to up my tax allowance from "1" to "2". Can I do this?

Wanting more in your paycheck is the smart way to go. You want as small a return as possible, and having to write Uncle Sam a small check is even better. Going from 1 to 2 leaves the possibility of having to write a small check, but you will not under-withhold to the point that you will be penalized for it. See how 2016 turns out and you can always go back to 1 next year.

Single/2 is the default if you fill out the W-4 worksheet. It's usually pretty good until you have $50K in income.

Yes if you have only one job at a time. You'll either get a small refund, or owe a little.

You can. You may owe a little when you file, but not much.

Last year my return was $600. I expect the same this year. Thanks for your help! I need more money in my pay check.

absolutely

yes you can

uh sure