Sorry I didn't answer sooner, but I just got apporved to post. Hope I'm not too late.
I own Jayco Kiwi 21c hybrid since 2001. Overall, it has been a great trailer. There are some issues, though, you should look for which have been somewhat universal in the Kiwi line.
First is the infamous Kiwi roof leak. Look around the ceiling in the front right corner near the foldout for damage. A LOT of Kiwi owners I know have had the same issue in the same area. It is basically a problem with water pooling and the caulk on the roof needing some attention.
I have just finished repairing the floor in the front storage compartment. The seals around the storage doors were not very good and have leaked over time, going under the vinyl flooring and rotting the subfloor. I had to tear out the rotten wood, replace it and put new vinyl flooring here. Look inside the storage compartments for discolored vinyl and a "spongy" feel to the floor under the vinyl.
I also had an issue once with leakage around the front fold out with leakage due to an improperly placed gasket. It was repaired by the dealer.
Otherwise, I have had no problems. I am right now interested in trading up to a Jay Flight, mainly to simplify my life and make setting up and breaking down camp easier.