Well that's where I have a problem. You say 'if needed', which tells me that if someone had not asked for cash (if they had no clue what they were doing, perhaps) you would not have voluntarily offered cash.
At least, that's how I'm reading it.
As for not being able to edit the post, I believe the timeframe is 90 minutes (could be less...might even be zero for that forum) so that people cannot come back and edit things for their benefit (i.e., they post that something is 'ok', then sell it, have a dispute with the buyer, then go change the post to say it was 'damaged').
No longer a BES Admin, but it was fun while it lasted!