Tips for golfing in Visual Basic
Use DefXXX statements when declaring multiple variables

The statement
DefDbl A-D

Defines all variables that start with A through D as being of the type Double, which means this can shorten cases such as
Dim A As Double
Dim B As Double
Dim C As Double
Dim D As Double

Similar commands exist for the following types
DefBool     ''  Boolean
DefByte     ''  byte
DefCur      ''  Currency
DefDate     ''  Date
DefDbl      ''  Double
DefDec      ''  Decimal
DefInt      ''  Integer
DefLng      ''  Long
DefObj      ''  Object
DefSng      ''  Single
DefStr      ''  String
DefVar      ''  Variant