Price check need bypass solenoid valve and two way valve b/c honda odyssey failed inspection. quoted me 300.00 problem: how so i know if this is a fair price?

EVAP system, leak detected.

possible causes: gas cap loose or damaged, hose, fuel tank pressure sensor, evap valve, evap bypass solenoid, evap two-way valve, evap canister, evap vent valve, wiring.

You can get a reman trans for about $2500 or rebuild yours
for $1700 locally

The misfire could be spark plugs & a couple of ignition coils
you do for $100

Egr about $80 you do

You need the trans diagnosed at a trans shop & road tested

I assure you they probally picked up on the problem while checking the trans. they would've used the Honda scan tool and checked any engine malfuntions before evaluating the transmission. you can, however, clean the idle/air control valve by removing it from the throttle body and using some air-intake cleaner on it. the cleaner is available at local parts stores. you may also want to clean the throttle plate with the cleaner to insure it is not sticking to cause the idle problem.

YOU NEED A TRANSMISSION REPAIR MANUAL. OR SOME TIMES SINCE YOU HAVE TO GO TO DEALERSHIP TO BUY THAT PART.THE PARTS DEPARTMENT SALESPERSON WILL SHOW YOU ON A COMPUTER THE PARTS LOCATION FOR SHIFT SOLENOIDS OR SHIFT SWITCHES ON THE TRANSMISSION VALVE BODY.

SYMPTOM
The MIL is on, and DTC P1457 [leak detected in EVAP
control system (EVAP control canister system)] is set.
PROBABLE CAUSE
The EVAP bypass solenoid valve can fail due to
corrosion. Replace the bypass solenoid valve first. Clear DTC's and test drive.

Depending on where you live, there prices are very good. Where I live, we can't find repairs for less than $78 per hour and body shops generally charge in the area of $120 per hour.

Normal maintenance schedule at 75,000 miles:
Replace transmission fluid.
replace engine oil.
Rotate tires.
replace engine oil filter.
inspect brakes.
check parking brake adjustment.
inspect tie rod ends, steering gearbox and boots.
inspect suspension components.
inspect driveshaft boots.
inspect brake hoses and lines.
check all fluid levels.
inspect cooling system hoses.
inspect exhaust system.
inspect fuel lines and connections.

(At 90,000 do all of above plus:
replace air cleaner element.
inspect and adjust drive belts.
replace cabin air filter.)

Ramon
P0420 relates to the catalytic converter. The computer sees little or no improvement in the exhaust before and after going through the converter. Either your oxygen sensors need replacement (3 total) or you need a new catalytic converter.
What is the mileage on the vehicle? Does it run well? Oxygen sensors generally start to fail after 70,000 miles. Catalytic converters usually fail because the engine is runnig rich and the owner ignores that fault for months. This causes the catalytic converter to overheat and fail.

P1456 relates to the evaporative emission system. This system holds the gas fumes in the system so they are not vented to the atmosphere. The most common cause of this code being set is failing to properly tighten the gas cap after refueling. Take the cap off and clean the sealing O-ring. Put it back on and tighten till it clicks 3 times. Make sure you have the correct gray colored gas cap. Clear the code and see if it resets within a few days. If it does, try replacing the gas cap.
Charlie