I was married in early September and my two favorite vendors were Cassidy Duhon (Photographer) and The Barns at Wolf Trap (venue).
Cassidy is so personable and we clicked right away - he has a great eye and unique ideas, and I never felt like there were hidden costs or sudden surprises. He was one of the first vendors I found, because, the way I figured it, you spend pretty much your whole day with the photographer, so it it ought to be someone you like and trust. If you like a LOT of posed photographs with family and the wedding party, he may not be the right choice for you - we only took a few posed pictures with each of the groups, and I was happy about it! Most of his shots were more creative and photojournalistic. Also, he is definitely one of the more affordable photographers we found in the area and I couldn't be happier with the 800+ photos he and his assistant took!
The Barns was a GREAT venue and Rosie, the coordinator, really knows what she is doing. We had a rustic, creative type wedding and The Barns was a perfect fit. It is easy to get to and there is plenty of parking, and it holds around 170 people, so our 100 didn't seem dwarfed by the space as it may have been in a ballroom setting. It is also more affordable than a lot of other VA/DC spaces, but you do need to use their bar services (no buying and bringing in your own alcohol). Rosie was on top of everything and served as a day-of coordinator for me, so that, too, saved some money since I didn't need to hire one! Highly recommended.
One other note, renting your own chairs through DC Rental is the way to go - I got a rate of $4.80 per chiviari chair, which was around $2 less than what my caterer could offer!