Blisters are caused by friction, plain and simple. You need to eliminate the friction and Vaseline is very good at this.
Cover your feet in vaseline, wear an old pair of socks on top and go out for walk in your new boots. It works for me.
It sounds to me like Toddy is suffering from a 'hammer' effect (I've had this too) - the heel slopping around in the boot and each step hammering into the heel.
This could be because the boots aren't quite shaped for your feet. Padding would probably be the best option here should you wish to stick with the boots.
"Mummy, when I grow up I want to be a bushcrafter."
"You can't do both son."