The same goes for eyewear. I got the exam, 2 pairs of frames and lenses with all the coatings for under $300 in Algodones three years ago.
My new glasses cost me $600 PER LENS, plus $85 for the exam. They wanted to sell me new frames too!
I told the receptionist that it was the very last time she would see me. I can fly to AZ, rent a car, get an exam and glasses in Algodones, spend a week in a hotel in Yuma eating out 2 X daily, and still have money left over when I get back compared to buying from the local optometrist.
I even figured out how to modify the prescription so I now have special glasses for welding, computers, carpentry, etc. for only $20 each. This is especially important for me since I had a cataract removed from only one eye, so my glasses have very significant differences for each eye. BTW, the $20 mail order glasses have always been exactly right. The only problems I've had have been from $400 glasses from the US.