If I read you right, this will be your first transaction. The good news is Virginia allows you to do this, secondly the experience gained by acting as a transaction broker you will gain incredible experience by doing this. I suggest you perform all the duties normaly associated with dual agency that come after the contract is ratified. It will cost you a few hours and a few dollars but the opportunity to develop a system to get to settlement is priceless.
Discuss it with your broker and then with the seller and hopefully you can come to a simple dollar figure. Think of it as training and ask your broker to watch and follow it through with you.
I think it depends on your state laws, check with your broker. I did this once before and charged a commission fee of 2% and made sure all the disclosure forms were signed and that both parties acknowledged that I was being a transaction broker and didn't represent either side. I simply got paid to do the paperwork and it worked out well. Actually, my firm got paid and then disbursed to me. Good luck!
Keep in mind that you are responsible for both sides of the paperwork (including errors and ommissions) and your broker may not approve of this.
Selling a home is not just about finding a buyer...it's about all of the contracts, paperwork, disclosures, and negotiations that go on after the fact, I personally would not do this. Talk to your broker first. (And welcome to the business!)