I drive a Toyota Prius. We are very happy with the car except for the
rear view. The blind spots are larger than expected and we would like
to install larger outside mirrors like the ones on a Toyota Highlander
SUV. Toronto customizers say this can be done but we will lose the
remote control function. Is it possible to install larger mirrors at a
reasonable cost while maintaining the remote? Can you give practical
advice on getting this done?

Perhaps you can install a couple of small glue-on wide-angle mirrors
in the corners of the factory mirrors.  The cost will be significantly
less, and it will give you almost an entire view of approaching
traffic from either side.

I tried that and found it unsatisfactory. Why should SUVs and Vans get
substantially bigger rearview mirrors than cars? We are all driving on
the same roads.

When it comes to car customizing you can make anything work. Any
custom shop should be able to put any mirror you want on there and
make the power angle adjustment work. All you need is the wiring
diagram from your vehicle and the one the mirror came from. You
probaly get it to work without them too.
    There are only about 4 wires that go to a power mirror. Any good
tech should be able to make it work properly. I suggest trying some
more shops.