In theory, you're absolutely right. There shouldn't be much difference, cost-wise, between renting X space for 5 people and renting X/5 offices. A rational rent

In theory, you're absolutely right. There shouldn't be much difference, cost-wise, between renting X space for 5 people and renting X/5 offices. A rational renter/buyer shouldn't have to pay a premium for 5 * X/5 vs X. But the 5 * X/5 configuration is not offered as frequently, or on comparable terms. It's all about the available inventory in the commercial real estate market in any given city. More often than not, if you're in the market for a space with any discrete offices -- regardless of their size -- you're going to have to "buy the cow" and rent a generally bigger space. That's just how office space is developed, rented, and sold these days. The open floor plan has become such a standard that one has to pay a premium to acquire the equivalent amount of non-open work space. Non-open offices have become something of a rarity, especially in the Bay Area. Typically they're rented to law firms, medical practices, and other professional associations: companies with lots of cash flow and a relative indifference to price, creating price-inelastic demand in the market.