You will have to decide how much time you want to spend boiling to know how many taps to have. With 10-12 taps, unless you have a few good runs in a week you won't be boiling long when you fire it up. I have a 2x3 and the first year I aimed for 40 taps. Earlier in the season the runs are smaller - 1/2-1 gallon/tap, so I kept thinking I could do more. Pretty soon I was up to 70. The first good run we had though, I found out that was too much like work! I decided that 55 taps was about right for the time I had to boil. Depending on how fast you boil you will decide how much time you will want to be boiling sap and how many taps you want for the size of your evaporator. Good luck with the new rig.