I agree with sall2009, well put sall (not sally).
Transparency leads to honesty & common knowledge, so why should certain subjects be hidden?
A number of these DIY Q&A sites (excellent as they are) have asonishingly petty rules. The internet is for everyone and anything, get it out in the open and talk about it. TV programmes discuss building work prices so why not us? I hate pornography but you are free to watch it. I hate drugs and drink but you are free to use them.
Less rule is best rule.
There are no 'rules'. The relationship between parties is very simple, an OP wants DIY advice, the trade offer their knowledge. The OP is doing the asking so is not in a position to dictate what the trade reply to. There is no obligation for transparency as no-one here is paying for anything.
In this instance Pedanticvindictiveman has highlighted the special breed of t**ser who frequently infects the site with questions about money. Many agree it's not what they want to advise on. Maybe the non-trade can discuss prices with eachother,
but don't come on here demanding anything of us. You're not our customer we've had nothing from you and owe you **** ALL.