This will ensure that your data is ready for immediate restoration should you decide to switch providers.
You should also have a competing ASP in mind and ready to hire in case some emergency should make an immediate change necessary. Contact your backup ASP periodically to make sure it's ready to step in.
Finally, make sure your contract clearly separates your property from the ASP's. Your domain names, licensed applications, and data must all come with you when you leave an ASP. Pay particular attention to the registration record for any domain hosted by the ASP, making sure that the billing and technical contacts are people at your company, not at the ASP or one of its agents.
True, signing with an ASP can help you free up capital and human resources for other projects, or at least keep you from being crushed by the burden of new applications. But don't forget that you're handing your most vital data to an outsider, so don't pass the buck too cavalierly. Establishing and managing a business-savvy relationship with your provider requires the same level of preparation as does any internal project.