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I'm guessing the £35 is the "activation fee" for the BT TV box. For legal reasons, they don't charge you for the box (unless you cancel early), but they do charge you an activation fee to switch on the service.
If you were taking over an active line - one with a dial tone - then you should not be charged the £130. That is only supposed to be charged for installing a new line, or for re-connecting a disconnected line. However, if Sky decided to be awkward and cut the line off before BT could take it over, then the £130 fee would apply.
If you think the charges are wrong, then complain to the billing department - see the Contact Us icon at the top of this page. There's a section for billing. Many people prefer Live Chat to phoning the Indian call centre, but it's not open 24 hours.