Thanks, Rosa! Based on your numbers I'm thinking maybe the $4 samples I was looking at were 0.6 - does that sound more logical for only $4 each?
6ml for $4 sounds about right.
The forum vendors have been vetted by our members, tried and true. If they start to have a bunch of complaints they do get kicked out.
It can be helpful to ask which vendors people like the best for specific items and you'll get a short list of places to look first. It's usually a good idea to get your equipment and juice from different places (juice vendors are good at juice, equipment vendors are good at equipment).
For samples I sometimes go here: FreedomSmokeUSA they have a lot of flavors to choose from, but you can't customize (most of) the samples themselves (all are 50/50 mix of PG/VG, all are 24mg) ... coupon code "freedomsmokeusa"