what you mention is a standard master/detail relationship
you require two datatables, one with the customer details, one with the work details for that customer. a relation will exist between the two tables because the work items will have a customer ID. if you plan on doing multiple sessions of work for a customer, then each job block might also need a group id that you set
CustomerTable
---------------
CustomerID
CustomerName
CustomerAddress
etc
WorkTable
----------
CustomerID
WorkGroupID
WorkItemID
TaskDescription
so you can have customer 123 who wants the light bulbs replacing and the carpets cleaning as part of springmaintenance:
CUstomerTable
--------------
123
Acme COmpany Ltd
1, ACME Road Blah
WorkTable
----------
123
SPRINGMAINT1
1
replace lightblubs
123
SPRINGMAINT1
2
clean carpets
if an updating event occurs that changes CustomerTable.CustomerID from 123 to 456, and a relation exists that is enforcing integrity, then all instances of 123 in worktable will become 456.
Is this what you require?
If so, have a read of the DATA WALKTHROUGHS (google that) on MSDN