For instance, Solds for single family homes in the past 3 months shows one of the lowest priced homes sold for $350.27/ per sq. ft. while one of the most expensive homes sold for $177.76/sq. ft. That's quite a range!
For condos, a lowest priced sold was $ $246.48, while the highest priced one sold for $216.19.
Upgraded kitchens, baths etc. don't always translate to higher sq. ft. price because so many other factors come into play - each home must be evaluated on it's own merits and what it has to offer in the overall picture.
I've found the best way to use price per sq. ft. is to evaluate comparable properties within a specific range. For instance, if you are looking in the $450,000 to $525,000 range you would check the price per sq. ft. in that range for all similar properties and check those numbers against amenities, location, etc.
Best of luck!
That said, in the past 6 months ... approx 108 properties sold ranging from $132K to $1M ... sitting on lots ranging from 1/2 an acre to none at all. The average of that hodge podge of properties comes to about $234 per square foot.
Are you looking to invest in Newburyport? To live there?
Let me know if I can be of more help.