Pre-qualification is an informal way to see how much you may be able to borrow. You can be "pre-qualified" over the phone with no paperwork by telling a lender your income, your long-term debts, and how large a down payment you can afford. Without any obligation, this helps you arrive at a ballpark figure of the amount you may have available to spend on a house. Pre-approval is a lender's actual commitment to lend to you. It involves assembling the financial records and going through a preliminary approval process. Pre-approval gives you a definite idea of what you can afford and shows sellers that you are serious about buying.
Use caster sets to keep your major tools, even workbenches, portable. Wheeled tools and benches will allow you more flexibility, and will let you reposition for specific jobs like ripping long lumber or for taking advantage of natural daylight.