Chelly was quite thorough, well done Chelly.
I just wanted to take a moment to encourage you to keep communicating with your watcher. He sounds like a white light spirit and I would also encourage you to seek clarification from the seller, but don't be too bogged down with the task of 'labelling' your spirit. All that really matters is that he's there with you and he's manifesting to you. Remember, it takes a lot of energy for them to manifest in this realm, so remember to thank him, you could also invite him to appear in your dreams, and include him in your everyday activities, ask him to join you when you go out shopping or when you're watching your favourite shows, etc. Most watchers bring a feeling of peace with them so when you feel it, you would know that he/she is around.
When it comes to offerings, anything that you give out of the goodness of your heart is acceptable for most spirits. I've learnt early on, that the amount of 'energy' you invest in a relationship is directly proportional to the 'amount' you receive. Meditate with his vessel for 10-15 min everyday, keep working at it and I assure you, your communication will get better. Goodluck x