Retrofitting a building to be more resistant to the force of earthquakes can be a very smart, cost-effective measure to save money in the long term. This is especially true in very seismically active areas. After all, the cost of regular repair work to a non-protected building adds up over time. The biggest skill you need from an earthquake retrofit contractor is the ability to build within existing structures. After all, you don't want to tear your whole house down and start from scratch. A retrofitting job requires a contractor who understands how to blend new features within older features in a way that is somewhat seamless. Even more extensive retrofitting jobs will require someone who is able to work around a pre-existing structure. This is not a skill that all contractors have, so you should look for it. You should also find out how much the job is going to cost you. Some contractors will be able to give you a general quote just by asking you some questions. Others will need to visit your home and work out a specialized plan with you before they can generate a quote. Since these retrofitting jobs can be very costly, it's important to know what you're getting into up front.