ACL surgery options?

Aloha, my 66lb mixed breed (poi) dog has a ruptured anterior cruciate ligament which requires surgery. My vet gave me an initial estimate of $2000. I scheduled the sugery for next week and then was called back and told the surgeons estimate is $3950! I was in shock but now have done some research and he wants to do the TPLO surgery (bone cutting and plates) versus the conventional surgery which is much less expensive. I have read about both and really can't find any reason to go with the TPLO (besides the vets making me feel like a bad mommy who doesnt love her dog!). My dog is 8 1/2 years old and just wants to be able to go for walks again--not extremely active. Any opinions or experiences with this operation would be great to hear before I talk with my vet about this. Mahalo!