NEW CABINETS FOR EXISTING APPLIANCES ?

Kay,

Thanks for the kind words and for joining our forum.
In answer to your questions;

1 Can we build-in or integrate our fridge, and our freezer, and if not is there a way of stacking one on the other ?

You can build in existing fridge and freezers if you install extended gables and deeper worktops than standard, not forgetting ventilation requirements.

As for stacking, this can only be answered by your manufacturer but if you are suggesting this inside a cabinet the answer is no, unless you maintain recommended clearances,

ventilation and install without cabinet doors. Not a good idea if you wish to improve the look of your kitchen.

2 Can we build in our combination microwave ?

Only successfully if your manufacturer produces a building in kit. Other than this you can build in providing you maintain the manufacturers recommended clearances. These clearances

may be so great that it renders the look anything but pleasing to the eye.

3 What are the pros and cons of siting the sink, or a hob, across a corner ?

The pros of fitting a corner sink are that it may allow greater design scope by freeing up space elsewhere in your kitchen.
In the case of a hob it may be a design plus if your kitchen is large enough. An extractor is an integral part of a corner hob configuration and to achieve this configuration you will

have to forsake space. not a problem if your kitchen is large enough.

The cons are that you will have two vulnerable worktop joints within close proximity to the sink, if you are installing laminate or wooden tops.
As you are spending most of your kitchen time in front of a sink, you may be staring at a wall as opposed to through a window which is a criteria that most designers aim for.
In all honesty though if it is your preference it is the right decision for you but think of the practicalities and base your decision on them.