Great Deal on a TT with a "small" leak
Hello Driveby
It is very unlikely that ceiling ripples would be caused by interior condensation. My guess is the ripple is just forward, or rearward, of the roof vent indicating a leak.
Whether or not the unit is worth purchasing depends on if the cost to repair the damage is considerably less than the discount they are giving. Finding the cause and repairing the damage can be very costly unless you are able to do it yourself.
Beyond the physical repairs is the ability to access and remove damp insulation, as that will cause mold and mildew problems in the future if not replaced. Unfortunatly, the parts that show water damage are usually only about 25-30% of what actually was getting wet between the ceiling and roof.
I guess I would advise you to stay away from that particular rig unless you have the ability to make the repairs yourself......then consider the value of your time versus the discount offered.
W