Didn't see the whole question from my phone. I would advise saving the money for the new home purchase. Also, now is a good time to think about your long term goals with the first house. I have 4 properties, I rent out 3. My goal is to keep them all (hopefully get more) so now I'm starting to pay down the mortgages on my other properties so that in 19 years when I'm 60, I have cash flow in my later years. I may not pay them off before then but I do plan to pay them down quite a bit.
You should also consult a tax advisor because there could be tax issues that can help you decide how to go about buying the 2nd house as well and as far as paying down the 1st one. I'm not sure if on investment properties you only benefit from depreciation or also from the interest deduction. I should know, but I don't. :) I have a great accountant too so I can refer you if you need one.
Please feel free to e-mail or call. I've been in real estate almost 10 years, and investor for about 8.
Good luck and you can't go wrong buying in Northern Virginia for sure!