To start with Bolivia is safe. I travel everywhere with a lot of expensive camera equipment, and Bolivia last year was no exception. The first couple of days I left it all in my room rather than carry it around, because I was worried about having it stolen. On day three I realized that even in Bolivia's biggest city there was a surprisingly small amount of crime. To put it simply, if you use common sense in La Paz you are likely safer than you would be in any major American city. The people are kind warm friendly and honest. No one on our trip had anything stolen or heard of anyone having things stolen. This does not mean we were careless, but I was no more careful here than I would be North America.
Bolivia is cheap. When I say cheap what I mean is once you get there it is really inexpensive to buy things. If you are willing to eat street food then you can get lunch for a lot less than a dollar. A good dinner at a very nice restaurant is likely $10. Hotels are also a good deal and there are plenty of hotels that would meet that standards of North America for cleanliness and comfort.
Bolivia is Beautiful. I don't need to say anything here. Just look at the photos.
Bolivia is fun. The people of Bolivia are some of the happiest people I have met. They add to the enjoyment of what would be a great vacation anyway. La Paz is a big city and the night life is a blast! Great bars, great restaurants and great clubs.
Bolivia has great trekking. Just look at the photos.
Bolivia has great climbing.
See you there!