It is essentially calculated as the interest rate times the outstanding principal amount of the debt. Interest expense on the income statement represents interest accrued during the period covered by the financial statements, and not the amount of interest paid over that period.
Even though my basement bathroom cost was around $3,700, you could probably do it for just under $2,000 if you really pushed the envelope, maybe even less. I'm not going to sugarcoat the project. From a time perspective it takes awhile if you're doing it by yourself.
Homeowners have many options when they remodel a bathroom and the total cost depends on style and budget. The average bathroom remodel costs $9,275, but you can spend less - between $3,500 and $7,000 - to fix up the essentials in a small- to medium-sized bathroom. On the other end of the spectrum, you could spend $13,000 to more than $20,000 on a master bathroom remodel to make it an oasis.