Wholesale Deal

When doing a wholesale deal and the buyer does not have funds for a 100k assignment fee, would putting an invoice in escrow be a realistic option to collect the 100k if so could someone please advise or if one has better way please advise

A 100k assignment fee? You might have some issues collecting on that - especially through escrow. If this is the fee, I think it would be best for the buyer to pay you outside of escrow.