Migrate and Maintain Wordpress Websites

Hi! Thanks for looking!

We are a marketing agency that has started offering Wordpress hosting to our clients. Here is our hosting website: http://hosting.designermd.net/

My goal is to do more than just host, I want to go in once a month and update Wordpress, themes, and plugins. In case updating breaks something we will have recent backups everyday and can perform the updates in a staging environment to test before we you live.

When a client comes on board we will be migrating their site from either 1&1, GoDaddy, BlueHost, or other popular hosting companies. A few may be migrated from a private server. We will have the login from the hosting companies and for the domain company.

Here's directions on how to migrate:
http://wpengine.com/support/migration-process/

If the client chooses the business package or higher, the next step will be to update every month and troubleshoot if a problem occurs.

What I need is a quote for migrating the site and a quote for updating the sites once a month. Trouble shooting will need to be included in the quote. This shouldn't be an issue often since we will have daily updates and a staging environment.

You can expect about 35 sites over the next 12 months.

To summarize I need quote for:
1) Flat rate for migrating a website.
2) Per site monthly rate for updating Wordpress, Theme, & Plugins. Average amount of plugins is 5.

Experience required:
Database
Wordpress Dashboard
WP Engine

Thank you!