Cat Urine Damage to 3 Stud Corners
I purchased a home about 10 months ago. The home is in really good condition but has had one major problem. The previous owner had a major issue with cat urination which is widely known to cause smells don't typically don't leave without removal of the soiled area. There are a couple of rooms in the home that have been taken through the ringer as far as damage to the subfloors and the drywall. After removing baseboards and pulling quite a bit of the drywall off, I discovered that the urine had soaked through to many of the studs, some of which are in the corner in a 3 stud configuration. There are also areas of the "sole plates" damaged as well.
Now I have some basic questions: Should only the bottom portion of the studs need to be replaced? Is this work I can attempt to do myself considering I have no prior experience with framing? If so, what are the recommended techniques especially for the 3 stud corner? If it is recommended I hire a contractor, what range can I expect the cost to fall in?