Is it appropriate to negotiate with customers via email?

Thanks 

Yes, it is suitable method when customer live out of your company location  

But this method needs more effort to approach your opinion. 

Negotiating over email can save time, result in more thoughtful trades, and ensure details are captured - 

Yes its depending on nature of negotiation. Some negotiations need to be proper document so email is a best source, some time one to one is most important.

Preliminary negotiation can be through email and this will give you an idea about opponents demand, and once you know opponents demand, the finals can be a face to face, there be with an surprise element never can be rejected by the opponent. However, if the opponent is not anywhere you can reach on a meeting, then, no other choice, emails cannot be avoided.

Yes ... I agree with Prof. Omar answer certainly Of course ... communicate with customers via e-mail ... new technology ... worthy follow-up to take advantage of them

yes but only when you can not meets face to face to close the deal

Thank you. I depends state to state. I thing it's not bad way.

Yes, I will entertain but there must be a follow up by calling the client and meet them personally to be able to have a formal negotiation.

Email  can be an important tool to start a negotiation as it helps break the ice between us and clients. Also, one can gauge the customer in terms of his needs and profile.

However, for a fruitful deal closure, Face to Face interaction is a must. It gives the sales/marketing person the best opportunity to conclude the negotiation with the best offer possible which would be of mutual benefit to both the parties and pave path for future business flow from  the same client.

Thanks for invitation,

Yes, since your customer are willing and accepting for such type of negotiation or to documenting the outcome of your verbal / phone negotiation.