It should be able to handle a max of 16GB. (8GBx2). You may want to just try the SSD alone first and see if the performance is good enough for your needs before you buy the extra memory.
There are three screws on the back of the fan. Remove those screws and you should be able to take the fan grill off. Once you get the grill off, clean it with water and a mild soap. Make sure the fan is unplugged while you clean it.
