Few people use an SSD for storage. A HDD is fine for most and certainly much cheaper. Why do you think you need an SSD? If it fits, and there is an extra SSD slot on the motherboard, you can install it. It will become a d:-drive, while your current SSD stays c:.
Assuming you checked that this PC supports 4*8 GB RAM, buy that. Or buy 3 * 8 GB of exactly the same make and model number of your current RAM (if that's 1*8 in stead or 2*4).
Should be no problem at all.
I want to increase my memory from 128SSD in my Dell OptiPlex 9020. If I buy a 1TB SSD, can I install it in the bay next to my 128? Will the 2 HD"s run simultaneously as one 1 1/4 TD? In addition I will add 24 more MB to the 8 that came with the set to total the 32MB max. Anyone see any dangers to these increases before I blow up my house?? Thanks, Harry.

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