That's outrageous and they're padding the bill with useless cruft - the "fuel induction service" and "throttle body service" are pure profit.

You're due, maybe even overdue, for spark plugs and coolant flush. Transmission should not be flushed. See the FAQ for details on whether the fluid should be changed with a drain and fill. (At 160K miles it may be too late.) Brake fluid change is probably not a bad idea but is overpriced.

Stay away from the dealer and find a good independent mechanic to service your out-of-warranty Toyota.

NO to spark plugs. Price is absolutely ridiculous. Iridium plug replacement is suggested at 100K miles, but 6 plugs and a gasket at $900 !

NO to transmission service. Your transmission has been neglected and no service will fix that now. It's best to leave it alone at this point. (and never allow anyone to convince you to flush your transmission)

NO to fuel induction, NO on throttle body service (First one's supposedly fuel injector cleaner in a can, quite common at all Toyota dealers, it's a great money maker, not so effective.. Second one is the Throttle Body; first you don't even have to take off a throttle body to clean it, only then would you use a new gasket)

NO to coolant flush, NO to brake flush. (If these haven't been done before, they are due)

This dealer is trying to take advantage of you, really that simple.

ALL of these things can be handled by ANY mechanic. So find a local mechanic, see what they will charge you to do all these services.. (without the transmission service)

You'll be far better off , as will your Avalon

- Spark plug replacement and gasket, air surge TA      $908

Maybe spark plug. Don’t know what air surge means. For the sparks, that seems way too high for an Avalon, even with the dealer up charge. I don’t think an Avalon engine is that complicated to be that expensive.

- Fuel induction service                                              $195

Fuel induction service is usually* a scam. It’s not really well defined. Sometimes it means sticking a bottle of cleaner in the tank and calling it a day (which you could do yourself for like $20 bucks.)

- Throttle body service                                              $155

While it is a good maintenance habit, if you aren’t seeing any signs that it is needed, you don’t need to do this. There are times where the throttle body might get stuck, and that is a good time to clean it. Also overpriced at the dealer. 

- Transmission fluid flush                                           $350

Eek. You’re at the mileage where it might be better to just keep your fluid rather than replace it. 

- Coolant flush                                                         $207

if this hasn’t been done by 120k, probably a good idea to do so. Still, the dealer is too expensive.

- Brake flush                                                            $265

if this hasn’t been done yet, it might be a good idea to do so. Dealer price is way too expensive .

Shop charge (not sure what this is)                            $50

They they tack on random fees to get more money from you.

Total                                                                     $2,130

Find a good independent mechanic. Or haggle down the pricing from the dealer for the necessary items. They are dealers, and like to deal.

How long have you owned the vehicle? If you bought it around 100k miles or higher, the transmission may have been serviced by the previous owner, hopefully at least.