Massey Knakal, whose bread-and-butter business is the sale commercial properties, has done a very neat back-of-the-envelope report on retail rents in various neighborhoods around Brooklyn. The Carroll Gardens market is particularly interesting given what a shopping boomtown it’s become. According to the report, the priciest patch of storefronts, not surprisingly, is Smith Street between Union and Douglass. Massey Knakal‘s Senior Director of Sales for the area Ken Freeman estimates that market rates for that stretch are between $85 and $99 per foot. Next most expensive? It’s a tie between the Union-2nd Place stretch of Smith and pretty much all of Court Street in Carroll Gardens, where rents are in the $50s and $60s. The cheapest rents (less than $50 per foot) can be found south of 2nd Place on Smith Street.