The UK Walton's Maintenance Packages is one of the most comprehensive on the market.
They are available monthly, quarterly, semi-annually or annually and can be cancelled at the end of any month.
The package includes:
Email and Telephone Support.
Monthly Full Site Backup including your Database.
Security Upgrades as they are released.
Continuous Site Monitoring.
Automated Currency Updates.*
5% Off Add-On Installations.
* On sites where Cron is enabled.