Getting one price then charged another...

Nismoracer

Went and had tranny fluid changed on my truck and rear differential. Called and asked dealer how much it would cost with my own fluids. They said $75 for tranny and $45 for the diff. Then when I go and they are done with the work they charge me $83 for the tranny and & $73 for the diff + $15 in shop supplies and tax. And I have 2 and half quarts of tranny fluid left and 1 quart of rear diff left. And they just did a drain and fill not a complete flush which I asked for. Told them I called and asked how much it would cost a couple days ago and they're response is no it costs this much. That's 3 dealerships now that I have experienced this with. I call to get an estimate and then they charge me more. What can be done about this? It's bait and switch.