Our real estate agent said that we need to pay 3% of the sale price , as out of the state tax.
We reside in Nevada , is that correct

To whom ? I am a real estate agent, ( although I use it for purchase and sale of mostly my own property) and I have never heard of this in Georgia. There is tax to pay on capital gains of the property

When is this suppose to be paid, who are they paying it to.

GA does have a real estate transfer tax, which is normally paid by the seller, but the rate is 0.1%. As Fr_Chuck noted, your agent may be thinking about your income tax filing for GA. If you have capital gains in the property you will have to file a non-resident income tax return and pay income taxes on the gain. The tax rate in GA is about 5%, not 3%. I suggest you talk to your agent and get more details as to what he's talking about.

Over the years the states have realized a lot of real property sales were not being reported by nonresidents. To correct this some states require income taxes to be withheld at the time of the sale. I think you will find out that is what this is. When you file the nonresident Ga. Return to report the sale you will then show the withheld taxes as a credit on the Georgia return and pay the difference or receive a refund.

Yes I will agree, it may be a income tax on the gains.

But again, make sure you have an attorney do the closing for here in GA. And as seller, you should be having one that is working for you.