what is a fair estimate of costs to rebuild/replace the transmission? on 2007 Nissan Altima

I noticed a "whining" sound about a month ago coming from the transmission. It was very faint at that time. I took it in and had the transmission fluid changed, on April 25th. Now, the whining has gotten worse. My son in law is an arm chair quarter-back/mechanic and he says it's the belts in the transmission. I've got the CVR (?) automatic transmission. Says they're wearing out. The car has 120,000 miles on it. I've had the trans fluid changed 2-3 times now.

Asked by for the 2007 Nissan Altima
Take it to a place like AAMCO for a free diagnosis and estimate, then shop around.
Hey thanks,

That's a great idea. But does AAMCO truly give free diagnosis and estimates?
They have to diag it to give the estimate and it's been free for a while now. Ask first for a free estimate. I had a place on Bush Hwy back in the early 80. To hot for me. Good luck.
Qualified Local Nissan Shops
Qualified Nissan Shops For This Repair
950 Airport Rd # 301
Technical Ability
Tools & Equipment
Customer Service
Customer Amenities
(254) 255-4268