What is the best way to offer discounts?

What is the best way to offer discounts?

I would like to offer discount categories to my customers.  For example, I would like to offer a neighbor to neighbor discount of 25% for local residents.  I understand I can do this through setting up price lists but what I found is that upon assigning a price list when creating an invoice, the invoice item only lists the discounted price.  I would like to have the original un-discounted price listed. then show a discount line with the name of the discount and the discount amount.  for example: 


#    Item & Description Qty Rate Amount
1 Svc_HR50
Residential Hourly Rate
2 $50 $100
2 Neighbor-to-Neighbor Discount 2 $-12.50 $-25.00












VBetter yet would be to have a subtotal and then the discount listed under the subtotal... but that might be asking for too much...or is it?

Than you in advance for suggestions and input.