Ubercart: Check to Buy

Hello,

I am wondering if anyone has seen a "check to buy" feature in the Ubercart checkout process? I am starting to notice this functionality appearing in other eCommerce websites (Amazon, iHerb, TaoBao) where you can place a product "of interest" in the shopping cart and then tick the box beside it when you want to actually purchase it. Example (TaoBao):

Example (iHerb):

Personally speaking, I like this functionality very much.

For those in the know:

1)  Does this functionality already exist in Ubercart somewhere? 2)  If not, how hard would this be to implement in Ubercart?

g.

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