If Me.Type1 = True and Me.Type2 = False Then
PCType = 1
ElseIf Me.Type2 = True and Me.Type1 = False Then
PCType = 2
ElseIf Me.Type1 = True and Me.Type2 = True Then
PCType = 4
ElseIf ... <further conditions go here>
End If
This is going on the assumption that you want to hardcode the value of PCType for every single different scenario (i.e. setting a different PCType value for when only check1 and check3 are ticked, another unique value when all three are ticked etc)
You can also simplify it further by using branching if statements:
If Me.Type1 = True Then
If Me.Type2 = False Then
PCType = 1
ElseIf ...
End If
End If
However it's hard to give examples of this based on the information you have given.