Calculation Workflows

I am trying to develop a couple workflows that will compute 2 calculated fields and produce the result for the purposes of charging fees. I want to use workflows instead of Java script if possible, is there a way to do this?

Interest Calculations:

Interest Rate = 18% per annum

Interest Per Diem = ((Interest Rate / 365) x Lien Fine)

Fee Calculations:

Number of Interest Days = (Payoff Date – Lien Recording Date)

Lien Interest Total = (Interest per Diem x Number of Interest Days)

Lien Amount = (Lien Cost + Lien Fine)

No Interest Accrued:

Recording Fee = ($10.00 + $8.50 per Number of Pages)

Training Fee = (1% off the Lien Fine)

Satisfaction Fee = ($10.00 flat fee per property)