This is the nicest laundromat you will ever go to. If you are a nice person and don't destroy things, you should come and enjoy this laundromat before the seedy element slithers in and trashes the place. The prices, which are a bit on the high side, should stave them off for at least a little while tho.
The guy that was running the place on Saturday night (9/2/17) was over the top friendly and funny. His name is Lee and he is literally a seasoned comedian that chatted us up for the duration of our stay. He is the regional manager so he's not always at this location. But if you do get to meet him, you're in for such a treat!
The front door does indeed lock at 9pm. My Angie and I started our wash at 8:30 but didn't see the sign saying you can't get in after 9. So we went to grab a latte down Sunset at Sunrise Coffee House (which is also delicious and very friendly). When we got back at 9:15, the door was locked. We simply knocked on the door and got back in, so it wasn't a major hassle.
For curiosity sake, I asked Lee if he knew of a 24 hour laundromat and he said that the only one he recommends is 24 Hour Laundromat which is at 3547 S Maryland Pkwy.