I couldnt agree more with all that was said.
The only advice i can give other then what was already said is...ask your mom why? find out her reasons and maybe you two can come up with a comprimise! maybe she's allergic to fur or maybe she had a bad experience. "because i said so" really isnt a reason but if thats what she says then there really isnt much to do, but find a way to comprimise and maybe in the end you two can pick out the perfect dog together. Puppies are alot of work...i have 3.
especially right now is hard for me, my youngest has something wrong and the vet cant figure it out, there's 2 vets working my case and they may be sending me to a specialist if the final test come back negative tomorrow. There's alot of unexpected things that happen, im sure you've ruled out alot of things but unless you've had prior experience with vets im sure the average first timer doesnt know how much vet bills can really add up.
Im at the vet @ LEAST 4 times a month, im lucky if i get down to 2 or 3 times a month. Very pricy
best of luck, let us know what happens!!