If you're using the shop as an office, rent the highest floor. It would normally cost between $800 and $1000 per month for 2nd floor or between
$1200 and $1800 per month on 1st floor depending on location.

Shops are normally sold by lot meaning if it is a 3-storey shop you'll have to buy the whole lot which would cost an average of $1mil depending on location. New shop lots would cost around $600K depending on location.

It is more practical to rent one.