Yes, and then you blow out all the profit with such services that you buy from 0% tax countries? How will this ever be believed?
If OP wants to save taxes, he should leave UK. That simple. He can go to Barbados, BVI, etc., manage his company from there and keep the warehouse staff in UK. Thanks to the DTA, he won't have to pay taxes in the UK anymore. All his other staff will certainly come with him and enjoy the beach life or they will be fired and replaced by more beacht characters from LSE or fiverr. It all is just a question of willingness. And if he does personal installations in the UK, well then that's exactly whe you do pay taxes there.