Best of luck with your move and welcome to DC!

That is a scam. Scammers "scrape" real photos from actual rental or sale listings and then post them on craigslist of FB marketplace at below normal rents. Do NOT give these people any money. We have a lot of people that move to the DC Metro from other areas and have to rent/purchase sight unseen so it's a common scam in this area. Word of caution - if it sounds too good to be true it is a scam. Another word of caution - if they say they are out of the area, or on a "mission", or they will mail you keys, or drive by and look in the window, or any other thing that is weird, it's a scam.

You may consider reaching out to a local Realtor to help you with your search.