Sum Values In Column Based On Condition In Another

II want to sum the values under 'amount' column only if the corresponding value under 'Balance' column is "Paid"

NameAmount Start Date End Date No.of DaysInteresetBalance
Sat1 250 1-Aug-07 20-Aug-07 19 - "paid"
Sat2 550 4-Aug-07 20-Aug-07 16 -
Sat3 250 10-Aug-07 20-Aug-07 10 - "paid"
Sat4 450 6-Aug-07 20-Aug-07 14 -

Total PAIDAMOUNT(B1:B4)

For the above, the sum value should be 500. I have written the following function to calculate the same. On uncommenting the line 'paid = CStr(paidvar)' the value is displayed as '#VALUE!'. On uncommenting all commented lines, the value is displayed as 'Paid'.

Function PAIDAMOUNT(amountRange As Range) As Variant
Dim count As Long
Dim paidvar As Variant
Dim paid As String
Application.Volatile True
PAIDAMOUNT = 0
For count = 1 To amountRange.Cells.count
paidvar = amountRange.Offset(count - 1, 7 - amountRange.Column).Value
'paid = CStr(paidvar).................