Not sure why you are going for 4TB but if it is a budget issue this 6TB drives at the moment are cheap:

https://www.amazon.com/gp/product/B07MYL7KVK

Make sure to select sold by Amazon:

New $86.99 FREE delivery February 10 - 13 Or fastest delivery February 8 - 9 Ships fromAmazon.com Sold by Amazon.com