# Lesson Six: Estimating Repairs, Part Two, The Default Repair Formula

Since this video (6:20) was made, we’ve had a lumber crisis and serious inflation. You can no longer build a house for $100/sf. Whenever you see this, figure the average cost of construction and begin with 25% of that.

We have updated our calculator to reflect these changes. You now first enter the cost of construction. Speaking of the calculator, here is your big BONUS for taking this course – a $100 value! It’s my Excel spreadsheet called FlipCalcs. Download the zip file here. You must own a copy of Excel for this to work. When you open it up, ENABLE macros. The macros enable you to clear data, move results to other calculators, and simply return to the main menu. There is one “Linked Offer Calculator” and several “Stand Alone” calculators, including the Quick Repair Estimate.

In the Quick Repair Estimate, you can enter the cost per square foot to build new construction, and then multiply that by .25 to get your “rehab multiplier.” This is for basic rehabs. I didn’t do the math for you here because you have the option to increase or decrease that multiplier based on the condition of the house.

There is a little shield icon on the main menu and with each calculator. This is a link to a video that explains that calculator fully. For more on all of this, see the course “FlipCalcs.” on our website.