Chrysler Repair: 1997 Sebring LXI coupe, half a day, timing belt

Question
I just purchased today (9-6-07) a sebring LXI coupe (2.5L auto trans) that has a leaking water pump, only when shut off. Is it a Do it yourself task or should it be left to a mechanic to change it? All sites recommend replacing the timing belt at same time as well. Just the task of backyard dismantle and repair is my concern, if it can be done in a few hours or would take half a day. Thanks, I love the car but just have this kind of luck with buying used.

Answer
by the book  some one that has done it b4   5 hours first time  8 or so.  and yes replace the belt as well.  I will be doing on on a 97 later on this week  on the side here in Atlanta.
The parts  at my cost was 500  because of the updated stuff that goes along with a new belt.