Approximate cost to rehab a building

[James Cinque]

I dont have much information and I know the question is very vague, however, i was looking to get an approximate price of rehabbing an apartment/office building. The building is 9600 sg ft and consists of 8 apartments and 5 store fronts. The building needs a new boiler, HVAC, electric run throughout and im assuming new sheetrock and flooring. the exterior could also use a face lift which constists of wooden siding. Any information is greatly appreciated. I am only looking to get a "rough" estimate of how much it would cost to completely rehab a building. Thanks.