How would you decide if you should build a "Products you might want to buy" feature on the Facebook Marketplace newsfeed?

I will answer this as a product strategy question:

Step 1- Clarify the qn:

1) Is this shown after the customer had added a product to the cart  or after a purchase or as soon as the customer logs in?

2) Is this planned for specific products or all products

3) Are the products shown similar to the product being viewed or could be a related product but not in the same category as the product being viewed?

Step 2- Describe the company:

Facebook has an estimated of 2.5bn subsribers and is the market leader in social networking products. Marketplace is a platform that allows buyers and sellers to come together to make a transaction supported by Facebooks ecommerce ecosystem 

Strengths- Large user base, Leverage existing platform for ecommerce, increased engagement due to ecommerce

Weaknesses- Sellers are unverified unlike Amazon hence any poor experience will also manifest itself on the overall Facebook experience.  Supporting systems like Counterparty gaurantee e.g. service gaurantee are yet to be developed

Oppurtunities- More than the revenue from transaction, Facebook benefits from a potential surge of advertising revenue of 1st party and 3rd party ad and a creation of a huge data mine of purchase behaviours

Threats- Facebook marketplace being embedded into Facebook poses a huge risk of poor experience affecting the overall Facebook product experience

Step 3: Strategic imperatives

1) Engagement

2) Revenue

3) User base

4) Implementation cost

Step 4: Strategic choices

1) Products you want to buy is implemented in a non-intrusive manner with only shown when products are added to the cart

2) Products you want to buy is implemented on the home page as soon as the user logs in

3) Products  is implemented only when requested by user

4) Products you want to buy is implemented only in special cases, where there are products available at a discount or at a lower price 

5) Products you want to buy is implemented only for ad supported products

6) Products you want to buy is implemented for products that are stored in cart and user is yet to make a purchase

Step 5: Evaluation of stategic choices

Step 6: Recommendations

Its recommended that Facebook implements "Products you might want to buy feature" with

a) Products you want to buy is implemented in a non-intrusive manner with only shown when products are added to the cart

b) Products you want to buy is implemented only for ad supported products

and then extend it to:

a) Products you want to buy is implemented on the home page as soon as the user logs in