Turn Excel/VBA code into DLL

I have an Excel file with some VBA code to do the calculation. The objectives are, 1. Protect the VBA source code 2. Make it run faster 3. Do not need to re-write the source code too much, maybe less than 10% I think the way to go is to turn the VBA code into dll. In your bid, you need to provide, 1. How you are going to do it and confirm me that it is the easiest way 2. How much you charge 3. How long does it take The bids with sample work will be considered first. Attached is my Excel file with some VBA code. It is not complete since some critical source code has been deleted. The final product is actually you teach me how to do it. 50% milestone once you are selected (remember to provide a simple sample work!!). The other 50% if you show me a working version of my Excel file. And I will release the payment once you show me how to do it.