Shutdown ADC sites

Hello,

At my client end we have 4 sites, SiteA, SiteB, SiteC, SiteD.

SiteA has 1 DC & 1 ADC and in all other sites ADC is there, Now customer wants to shutdown all other sites (SiteB, SiteC,SiteD). Please let me know how I can proceed on this. 

Second - SiteD is not in sync with all other sites form last one year. How I can tackle this, As this is new customer  for me.

Please let provide your thoughts and suggestions.

Regards,

Manoj Rana

MCSE

Warm Regards Manoj Rana MCTS