Paper models can be very useful, but even with thick card stock - they don't tend to be very durable.  If I have a paper model that I want to modify or use a lot, I make it out of sheet styrene (plasticard).

Print the model out like normal and than you can either glue the pattern on the card or use carbon paper to transfer it to the card.  Cut out the parts  and glue it up.  Ignore the fold lines - it is normally easier to just glue the edges together than to try and get a good fold with the plastic.  Also, the tabs are not needed either.

You can use various epoxy putties to add additional details and also use normal plastic model parts or scraps of styrene.  Prime and paint like any other plastic model.  The end result is very durable and will last a lot longer than paper models getting the same amount of use.