Recently special ordered an i7 Asus with 16GB of RAM and other specifications for just under $1,000 through this Best Buy location. I told the sales rep that I was going to need 32GB of RAM, and he informed me that this could be added once the PC arrived. No problem; however, when the computer arrived in the mail, they then discovered that this particular motherboard could only handle 16GB of RAM and that no additional RAM could be added. I specifically chose this computer because of the fact that I was told I could purchase additional RAM. I was disappointed to find that Best Buy could not meet my expectations.
Definitely do your own research before buying bigger ticket items, and do not rely solely on what the sales reps tell you.