Venmo is instantly reverisble much like credit debit. This is one of the most DANGEROUS ways to sell bitcoins and is favoured by scammers. We discourage using Venmo unless it is for very trusted trade partners.
Buyer is not responding and my money was reversed back to them via Venmo. Would like to work out other pay arrangement or get my Bitcoin back. Currently they have my cash and Bitcoin . I'll update if this changes