Hi there , With us been pretty new to caravaning we bought a 1989 Swift Challenger 440/4 just to see if we liked caravaning we got the van fairly cheap but have modernised it with new chrome handles new carpet and curtains . The van looks great and loads of people have said how nice it looks but the bathroom area is a let down its a horrible green with a porta loo I would like to know is it economical to fit a cassette toilet and rip out the old green bason/shower as we never use the shower as it uses far too much water .Has anyone fitted one and is it fairly easy ? I am technically minded with myself been a joiner .