How to you more secretive stoners get good concentrates in DC?

Seems like most of the wax/shatter/resin/oil suppliers in DC (district connoisseurs, terpy solutions, silly bees etc) stick to vending at 420 events around town rather than doing one-on-one donations or deliveries. I'd love to get into that smoke sesh scene but can't because of work--have to keep my consumption a little more low-key.

Anyone found sources with good quality/varied concentrates who'll deliver or do a discreet meet? Bonus points for having strains without mega sleepy/couch lock effects.