In city Shanghai, there are two major areas in metro Shanghai for foreign companies to consider leasing Grade A and B offices: Puxi and Pudong

Puxi 
Nanjing Rd area
Huaihai Rd area
Bund area
Xujiahui area
Hongqiao and Gubei area
Pudong
Lujiazui area

Office space leasing companies normally provide only the shell office with ceilings, walls and safety fittings (e.g., fire sprinklers).
Tenants normally have to hire an office contractor to do the finishing out (decoration), install phone systems and get the furniture. But sometimes, businesses interested in leasing office space might get a office that has already been finished out (by a previous tenant). Since the needed decoration has already been completed, it might suit the style that you want and it could save some expenses as well.

Also, office management companies normally give one month free rental for leasees to do the renovation and to arrange other details.

c. Historic warehouse office and garden house office 
Shanghai office space is still dominated by high rise buildings. But with some renters, especially those in advertising, architecture design and culture communication, it has become very popular to take office space in historic buildings, garden houses or warehouses.
In Shanghai, the most famous warehouse office places are the Liftstyle Center close to Fuxing Park on Jianguo Rd., a warehouseon Wukang Road, and also old warehouses in the Suzhou Creek area.
However, renters should also understand that availability and locations are limited. There are not many options for renters trying to rent warehouse buildings simply because demand is high and supply is short.
Also, not all of the old warehouse offices are authorized by the Ministry of the Foreign Trade Committee of Shanghai.
Historical warehouse style buildings are available only in the Old French Concession (Xuhui district around Huaihai Rd.), Nanjing Rd. (Jingan district) area and the Bund area (in Huangpu District).

The size of the office.
In China, it is standard practice to calculate office size based on gross area, meaning that the size of the office includes a certain percentage of the area for walls, public hallways, and lifts. Office efficiency rate (the difference between gross area and net size, i.e., usable area) is normally from 50%–72%, and we suggest that clients pay close attention to the relation between gross size and efficiency rate since the efficiency rates in different office buildings are very different.

But please remember that the office lease price is based on the gross size, not the net (usable) size. (The same is true also for residencial property.) However, in Shanghai offices provided through business centers (i.e., serviced offices) and a few Grade A and Grade B offices calculate office rent based on net size rather than gross size. A professional real estate agent for any office property should provide clients with a clear listing of details of the office property information.