There are plenty of places that apply tint film to auto windows,it looks
good,lasts a long time. You need to pick a reputable company,preferably one
that doesn't apply it outdoors where dirt gets under the film,causing
bubbles.

You might do well with the pull-down shades sold at chain auto stores. We
used them when we had wee ones and they made a huge difference, especially
since we were in Phoenix.

Mike

I have an 05 CRV with tinting over the existing tinted glass.  It does great
in the day for the sun and heat  (I'm in FL) , help with glare and is so
dark, you really can't see what's in the cargo area.  In fact I don't need
to worry about changing the rearview mirror at night.    However, keep in
mind that the extra tinting over the already tinted glass can make it harder
to see out the back at night.  Since there are a variety of tint shades, and
you should be able to get an idea of what'll work best for you.

$$ wise, the pull down shade might be the cheapest route to go, especially
if you think the darker tint will be a problem driving at night.