hi there
please tell me you are not considering it.
we really must be trying to sell up,
yes there are the bish, bash, bosh mob, that will run in, and run out again.
ive seen it in the past.
you have your insurance, your equipment and your chemicals to consider.
and then the labour time.
you need to establish a relationship with your client, where you specify an amount f work to be done, anything over the top of that, and you need extra money.
regards
martin