Secure RV storage in/around Washington DC

Holly Acres in Woodbridge, VA would be my choice.

Looks like it costs $195.00 monthly IF they have space.

Boat and RV Storage

You may have some luck here although it'll cost in the same price range as Cherry Hill. Still, it'll be in town with you and you can just hop in and go when it's time to leave DC:

Union Station Parking

Also do a search at yelp under "RV Storage" and a google for "RV and boat storage near Washington, DC".

LarryJM wrote:
I would second Cherry Hill. While a tad more expensive than some alternatives like local parks/CGs you could explain your situation to the staff and I bet they would at least look out for your unit while you are away and you would have a two way contact available for emergencies. Your neighbors I bet would also keep an eye on your unit while you are absent. I used to do the same when we visited relatives in Chicago and stayed at the KOA out past Elgin and was gone each day from sunrise to sunset.

Larry

A standard (basic) RV site at Cherry Hill, according to their website, costs $70/night. A site at Greenbelt NP is $20/night (it seems it's gone up since last year). I personally consider $50/night to be a significant difference in cost. That's not to suggest that it's not entirely worth spending the additional money, at least in some circumstances, and perhaps the OP's may be one of them...or perhaps not.

Given what near DC places are going to charge just for storage it might be worthwhile to look further out for a much better short term storage rate. Maybe a RV dealership if a storage yard cannot be found.

How about the Washington DC KOA in Millersville, MD?

I would second Cherry Hill. While a tad more expensive than some alternatives like local parks/CGs you could explain your situation to the staff and I bet they would at least look out for your unit while you are away and you would have a two way contact available for emergencies. Your neighbors I bet would also keep an eye on your unit while you are absent. I used to do the same when we visited relatives in Chicago and stayed at the KOA out past Elgin and was gone each day from sunrise to sunset.

Larry

Near to Cherry Hill and much less costly (and sporting fewer amenities) is Greenbelt National Park. If you don't need hookups for the time, it might be a possible option. You'd be wise to check on their policies regarding unoccupied RVs; I don't know if they'd be permitted offhand or not.

Have you asked Wyndham if they have parking/storage available for your trailer, or if they can recommend some place nearby? Chances are you're not the first to arrive with a larger than typical vehicle.

Cherry Hill Website

Cherry Hill RV park might be a good choice.