Though I am in the US, I do have some advice. Get a lot of price quotes. I had prices ranging from $30,000-$52,000 for vinyl siding and replacing 24 windows, adding a bay window and replacing sliding doors. The large commercial companies were much higher and I ended up using a small, local contractor who is a friend of a friend. The job was done for $32,000 in the end as I re shingled 2 smaller/lower roof pieces in addition to the original job.
Ask people who they have used and get everything in writing. Pay 1/3 upfront, 1/3 halfway, and the last third at the end. Do a final walk through and have them replace all moldings and blinds along the way. This is the type of small stuff they never come back for.
Move all stuff away from windows, b/c if they move it it will be all willy-nilly. Make sure they vacum up too. Overall I had a good experience.
GOOD LUCK!!!!!