Just wondering, do we know what the budget is for the series?

In classic Who it was a million quid a season.

I am sure its now a million quid an episode.

Yes, Moffat once said 700,000 from the BBC and 300,000 from merch sales per episode

£300k from merchandising per episode? Wow. Maybe naive of me, but I had no idea that it was churning this much cash from merchandising. Guess it makes sense why they tinker with the Doctor's costume every now and again per regeneration - more versions of the Doctor doll to sell etc.

I wonder how much money the Power Ranger Dalek models made...

Had cutbacks hasn`t it? It used to be a mill but IIRC is now down to 700-800k.