Even when in the past I worked with builders, I still passed the documents directly to the owner of the property ..... and still do now
I did at the time a few years back, correspond with the "office of deputy prime minister" with my concerns, the reply was that I pass them on to the person ordering the work, if that was my main contractor it became them. They should be instructed to pass them on to the end customer.
The point I was trying to make with the ODP was that the end customer needed to register the guarantee provided by the scheme and this included the total cost of the electrical works by me. I would charge the main contractor X amount and this should be the cost of the works for the guarantee.
However the main contractor might well add on Y amount as his cut and so the charge to the customer would be X + Y = Z amount.
Of course the customer was only aware of the amount the main contractor would invoice them and that could be quite unrelated to the amount I charged for my works.
Example - my 3 usual main contractors had differing concepts.
Contractor 1./ would usually charge my invoice without any additions but with a few jobs if he was in danger of losing out he would add a percentage onto all his subcontractors amounts by 1 to 10% if he considered that the end figures would still be reasonable and he would advise me that he had done this, after the event.
Contractor 2/ Would always add 10% or £100 and even try (clumsily) to hide the fact from us.
Contractor 3/ would usually but not always add around 5% but extremely occasionally add around 25% . However he would state that he does not usually add a mark but if asked on a particular job he usually stated a lower percentage than the one he actually had charged.
Around 70% of my subcontract work was with Contractor 1/ and the remainder with the other two.
(Sometimes they would ask me to invoice the customer directly, sometimes invoice them and sometimes invoice them for some of the works and the customer directly for other parts of that work or for additions).
Anyway the ODP insisted I pass all documents to the person who requested me to do the works, so I did.