guys i've seen over 100 parked domains with pr3+...how do they do it?are they good for buying?would their pr decrease once content is added?thanks
PR is never a good reason to buy a domain. If the name is one you want or has a good marketable possibility than it is worth buying. PR can be manipulated.
Those parked domains are most likely expired domains, which previously had pagerank and then they expired and changed owner. The new owner has registered the domain and has parked it. If the domain will still have backlinks, it is possible that the PR will remain, but not necessary.