Have a read of scops for advice on worming and the science behind it all. It is an excellent resource for vets and animal owners alike.
As a vet, I'd recommend a chat with your own vet about it because they can tailor worming to your area and your animals, which is really the only way to do any worming plan.
As for faecal sampling - vets in house, the online companies or home testing kits really only do gutworms and coccidia. Fluke and lungworm can be tested for by the vet labs such as sac.
If you are worried about resistance to wormers, your vets will be able to advise when to sample pre and post worming to check for resistance, which varies depending on the wormer.