Installing a washer/dryer combo.?

We are buying an RV (husband is retiring in 3 months.) He wants to purchase a washer/dryer combo and install it himself.
It is ventless. How hard is it to install.?? Where we saw it was an RV accessories store and they would install it for us but is $1034.00 plus installation.

Then I checked around and I found one on Ebay and they ship free and have a 5 year warranty. Also we save about $500 and we could use the extra money for other things. Thank you.

it would depend on the brand and model but all the sites i just looked at did make it seem to hard the all just said it just has to be hooked up to a water line