O&P, or overhead and profit, is a term used in the construction industry to describe the markup charged by a contractor on top of the direct costs of materials and labor. The O&P rate can vary widely from one contractor to another, but is typically around 10-20%.
Some people view O&P as a necessary evil, while others see it as an essential part of doing business. After all, contractors need to make a profit in order to stay in business and provide their services. And if you're getting a good job done at a fair price, then the extra few percent for O&P is worth it.
At the end of the day, it's up to you whether or not you want to pay O&P on your construction project. But if you do decide to go ahead with it, just make sure that you understand what you're paying for and that you're getting value for your money.