Dear Sir/Madam,
please let me introduce myself briefly. Fifteen years dealing with information technology, I am mostly familiar with fields of web development and system and network operations. My main responsibility is the complete, iterative design, planning, specification and management of the whole IT infrastucture at several midsize companies.
For tasks similar like yours I mostly do a full system backup in advance, and another sync when the website has been stopped but the server is still available for administration. This way the main backup can happen during normal operation, and the reinstall can start after the second data syncronization, which is a much quicker process than the first one.
For the backup I can provide you the necessary space for the time needed and I can sign a contract if you want that I'll delete all of your data after the production system is running again. Please let me know if any kind of database is running on the server as it may be better the back it up another way.
Please note that I'll need SSH and sudo access for the server.
Having any questions please don't hesitate to contact me, I'll be glad to answer them. I'm looking forward to work with you.
Kind regards,
Robert.