You told us these things were changed at 50,000 miles and that was 27 months ago. Nowhere did you say how many miles you have gone in that 27 months. Perhaps you should read your own posts to make sure the info is all in there.
Toyota says the coolant in your 2014 Avalon is good for 10 yars or 150. 000 miles unless it has been changed and then it is good for only 5 years.
My 2012 Camry has electric steering, I imagine yours is the same, so no fluid to change.
Toyota claims transmission fluid is lifetime unless you get a light for it on your dash.
My owners manual does not mention brake fluid.
Most posters on here recommend tranny fluid change every 30 to 50 thousand miles and brake fluid every 3 years.