There are readily available comps -- including cap rates, price per unit or price per square foot in Sacramento and Stockton. Gross Rent Multiplier might be a great proxy for you. I would recommend that you contact a commercial and investment real estate broker who speicalizes in the property type and the neighborhoods that you are considering.
Also, I would suggest that you consider purchasing one of the commercialy available market reports from Loopnet for instance for a market area.
Frequently, in the apartment market , since operating expenses are variable and managment practices are different, buyers and their advisors will use Gross Rent Multiplier as a substitute for Cap Rate. Gross Rent Multiplier or GRM is a ratio of Gross Rents to Asking or Sales Price.
Good luck! There are plenty of reliable information sources out there from active professionals in the Sacramento and Stockton Markets.
May 31, 2010