If you want to trade, chances are you already have a shop in your CAMP. Delivering your caps requires you and your buyer to be online at the same time. Set up a time and place to meet with them so you can deliver their caps. Remind them that they might have to bring an item to trade for the caps, which can actually double as assurance of their identity.
Speculations that players may craft robots to manage their shops while away abound. It could be another way to deliver the currency. In that case, give your buyer the location of your shop/robot, and let the NPC handle the transaction. This is especially useful if you can't handle it in person. However, this is still unconfirmed. Check back once the game comes out of testing!
If you're not sure how much to ask for your hard earned caps, looking at other players' offers as a baseline is a good idea. Otherwise, just go with how much you think the time and effort to collect those caps are worth. Market prices are always shifting, so check back often if the prices aren't to your liking.
Good thing PlayerAuctions has a market price tracker. Other than that, we have the PlayerGuardian system that encrypts and protects sensitive information. Then we have an interactive community of buyers, sellers, and our customer support representatives. Also, we don't ask for a subscription or other hidden fees. All that is why you should sell on PlayerAuctions.
Go and sell your Fallout 76 currency for real money now!