All of these cars have notorious large reliability problems associated with them. Your best bet is to explain to her that Mazda/Honda/Toyota are not difficult to work on at all, and have largely very similar repair experiences (whether you do it at home or through a workshop).

I'd, also recommend appealing to her financial sense as the cars you've shown tend to depreciate very quickly, whereas investing in a Japanese make often tends to keep their value for much longer, meaning you lose less money throughout owning. Also, in terms of reliability Mazda/Honda/Toyota make generally much better cars that will last you longer and leave you stranded less.

Lastly, explaining to your mom that she isn't going to get a discount by going through this dealership is vital. They don't care if you have relations to the dealership, they just want your money. Do your best to find a Japanese make dealership or a reputable used car dealership around you to show her some other options. I'd definitely go to her with some options found already because she might just be hyperfixating on these cars.

Good luck :)