Shaun,
Just read your query, and everyone's answers.... Now I'll give my spin on your dilemma, ...haha!!
First off, David E's (Ming's) answer is the closest, in both money terms and the actual situation as regards to Peggy being previously married.
I will add a little something here, If you start by giving large sums of money, it will come to be expected each time there is a Red Envelope situation. It's not a derisory remark, it's just the way Chinese are. (Something along the lines that Dave's Ming was intimating in her comment.) You can tell them all that your not a wealthy man, for a month of Sunday's, but if you give a large sum of money in a Red Envelope for a relatively minor occassion, they WILL consider you Wealthy Shaun, ... Guaranteed!! ...So start as you mean to continue is my advice!! ...haha!!
David.....