Dave
before you start to use peel away ask the client what they wont done to the floor after you've taken the old varnish off.
My exp with peel away has always been on brick/rendered surfaces,wood is a different issue,it still requires you to wash it off with water,this will not do the joints of the boards anygood,and may take ages to dry out.
You can hire a small flat surface sander with a vacuum attachment that with min the dust.
Pop along to your local Brewers paint merchant and ask them about FS10 its good stuff but expensive.
Please keep me up to date if you do this as i'm interested on how you get on.
Been there seen it done it
Chris