Made these changes, unfortunately still won't work.

'Worksheet code--------------

Public Money As Double

Sub StartButton_Click()
Money = 100
End Sub

'Worksheet code--------------

'Userform code--------------------

Public StoreMoney As Double

Sub UserForm_Initialize()
StoreMoney = 0
StoreText = "$" & StoreMoney 'This shows $0 in the Userform text box
End Sub

'Macro that sets the value of StoreMoney to 75

Sub BuyStuff_Click()
MsgBox (Money)
MsgBox (StoreMoney)
If Money = StoreMoney Then
Money = Money - StoreMoney
Sheet1.Range("E9") = Money
Else: OK = MsgBox("You don't have enough money!", vbOKOnly, "Not
enough cash!")
End If
End Sub

'Userform code--------------------

I get three MsgBoxs:
Blank
75
You don't have enough money!

Money variable is still not availible to the userform macro.
In the Userform (general) I wrote: Public Money As Double
This just gives a 0 in the first MsgBox.

Any ideas?