I think the best way to do this is this.
Code:
Dim strAccountingEmail as String
Dim strHREmail as String
Dim strAccountingSubject as String
Dim strHRSubject as String
Dim strAccountingBody as String
Dim strHRBody as String
Now that have these string variables you can assign them to values that are on your form.
On the DoCmd.SendObject function in your code you can then pass the string variables as arguments to it. The way you would declare the DoCmd and the way you pass the variables to it really depends on if all the services would receive the same information or not. The only to really know is if you could post the file you are working on. You could also add DoCmd's programmatically if the user selects multiple services. Hope this helps.
Chris