A quick method for estimating replacement cost of your home is to multiply total square footage of the home by current, local construction costs per square foot. (homeguides.sfgate.com)
For a quick estimate of the amount of insurance you need, multiply the total square footage of your home by local, per - square - foot building costs. (iii.org)
In 1990, 25 % of square footage of the home is converted to an in - law unit, and first rented in 1991. (money.stackexchange.com)