Yes, I think you have a great shot! The income will be based off of the last two years W-2's. So the adjusted income is what will matter. I am assuming you will be building on the 4 acres. It helps that you already own that. When you choose a lender, they will give you a lot of information. If you have anymore questions at that point, or wonder if you should shop around, let me know.
Definitely go local. They are easier to work with and are more familiar with local programs that you may qualify for. I would get pre-qualified as soon as possible to see if there is anything you need to work on to ensure that when you are ready you get the best rate. Some factors to consider are debt to income ratio, income, time at current job, etc. Your builder may already have a lending institution that they prefer. If you need help finding a builder or lender, let me know.
I would use a realtor if you don't feel comfortable. Let me know if you would like me to find you a good one in your area. The seller pays them for you anyway.