This is a complex question, I would advise you to sit down with an attorney to make sure you get this right. It might be beyond what can easily be answered in this box.
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In New York, typed names and/or signature blocks in emails are considered validly signed writings. However, your situation may be different. You would need to authenticate that the typed name in the agreement was typed by the service provider. A scanned or faxed signature would be preferable.
The information provided above is for general purposes only. It does not constitute legal advice or create an attorney-client relationship. Seek competent legal representation, because the facts of each case are different.