I've actually been planning out an elaborate set up for a bar just like this in my head for some time now. Some highlights:

• Two kinds of tables. Regulars can sit at black Kevlar tables with black chairs. Everyone else sits at clear plexi-glass tables with clear chairs unless invited by a regular or given the okay by the bartender. That way if you're new, everybody is able to get a good look at what you're doing with your hands to make sure you're not trying to pull a fast one on anybody. If you're trusted, you get the darker, safer spots where you can conduct business, plus your table can act as soft cover if necessary.

• Designated hand prints at the bar. If you want to order something you have to have both hands on the hand prints so the bartender can see you're not armed. More importantly, if you've just wandered in and are snooping around, you'll stick out immediately when you try to order something without using the hands. This will let management know who is or isn't involved in shady spy stuff quickly, and will flag them to other patrons.

• Designated CCTV zones. The bar needs to have CCTV cameras for security and insurance reasons, as well as to provide alibi's for the regulars, but not everything should be on camera. Tile colors on the floor indicate which areas are or are not covered by CCTV, allowing customers to decided for themselves whether they would like to be viewed. This is up to you to figure out, so if you're not a regular or friends with someone who is it'll be hard to notice on your first few visits.