
In the receiving area, you should determine:
- How many receivers do you have?
 - How many hours per week are spent on receiving?
 - How many clerks are entering receiving data into a system or processing this information manually?
 - How many documents are processed or produced per week?
 - How many workers or hours would be eliminated having a warehouse automation solution?
 
In the area of quality control:
- How many workers are performing cycle counting? How often?
 - How many searches are done for missing inventory?
 - How many clerks enter warehouse transactions, such as the cycle counts, or perform putaway?
 - How much time can be eliminated after the implementation of a warehousing solution?
 
In shipping:
- How many workers are picking shipments and for how many hours?
 - How many errors occur per week in the picking process and how many hours does it take to correct one error?
 - Determine the savings for this process improvement.
 
Total the savings by applying the weighted cost of labor (including benefits & taxes) for each of the various worker multiplied by the hours saved per week.  Total the savings per year and apply it against the cost of the warehousing solution.
I know this can feel a little overbearing for someone conducting an ROI analysis on efficient warehouse solutions for the first time.  Feel free to contact me at rich.reidman[at]l-tron[dot]com for more help on this ROI calculation.
Photo used under Creative Commons from toolstop.