2
Intersting !
All one to one relationships , business partners & some companies enter with written contracts with their clients...which is a Seventh house matter.I wonder , in a mundane chart of a nation , how citizens, which should be considered at its subjects ( or employees , then house 6? )are denoted by which house( frankly , iam guessing , house 7 here also)

For a businees house , house 11 should be its aspired goals of reaching successfully in international markets or ideals of Corporate Governance , (how clients be friends or hopes)

Anyway , Good question, Miss Leo!
And my thanks to you for this,
& best wishes!
arihant

3
With every customer there is a business partnership or 'deal' taking place. So I would use the 7th house as the house of one customer in particular or 'the customers' generally.