I have a 2000 Honda Accord LE with approximately 90000 miles.
Our car dealer says that we should replace our timing belt now for $700-800.
Do I really need to do this???
Yes, you do need to do this. You can save $300, or so, by taking it to an independent shop.
Only if you want to prevent the engine from self-destructing when the timing belt snaps.
If you check the mfr’s maintenance schedule, you will see that it needs to be replaced at 7 or 8 yrs., regardless of odometer mileage. You can get the belt and the water pump replaced for $600.00-$700.00 now, or you can wait until the belt snaps and spend that money PLUS the cost of replacing valves and pistons when they collide. In case you think that the belt will give you some kind of warning before it snaps, you will get no warning before it snaps.
Timely maintenance is invariably cheaper than the repairs that result from lack of maintenance.
The answer is in your glove compartment.
Timing belts have a limited life, 90,000 is about the usual recommended replacement miles.
When a timing belt breaks, they seldom give any warning, it just happens, and when it happens the engine stops NOW. You can loose power steering and power brakes. I repeat, you usually will have no warning. Some are designed so that there is no additional damage, but most offer the very serious risk of some very expensive engine repairs. I suggest you have it replaced.
Note: Car dealers are no better or no worse than independent mechanics, but they almost always charge more. The one place you want to avoid are chains, especial those connected with quick oil change places or big time retailers like Sears.
Note2: Get the water pump replaced at the same time, they last about the same time. Replacing a water pump while you are replacing the belt is easy and cheap. To do it a week later will cost you almost all the same labor a second time.
Doesn’t this make you wonder whether Honda’s other maintenance requirements have been adhered to by the OP? It never ceases to amaze me how car maintenance seems to be such a mystery to people when, as you said, the answer sits in their glove compartment. And, this requires no technical knowledge–only the ability to read the book that has been provided by the manufacturer.
The belt should have been replaced about 3 years ago. You don’t “really need to do this” if you’re willing to keep gambling on your engine.
Eventually your engine is going to show a royal flush and the card game is over.
If they follow the “don’t need to do it” advice, I wonder if they’ll post back here complaining how their car needs a new engine because the timing belt broke. 
this does not answer your question directly but i just replace the timing belt in my volvo for $300.
Your original belt is good for 7 years or 105k miles, which ever comes first. Since rubber deteriorates with age, do not overlook the 7 year limit. This is an interference engine, a broken belt will do about $3-4k damage. Have the timing belt, front oil seals, water pump and balance shaft seals all replaced at the same time and you will be good for 7 more years of trouble free driving. Compare that to the cost of a new car, its a real bargain.
This should be done by a reputable dealer. Few independent mechanics have the specialized tools needed to do this on a Honda. I have replaced many timing belts, but my Honda went to the dealer for this.
Its game over if the timing belt breaks. Can you afford the cost of a new car?
All the above comments are correct. I would emphasize the independent shop,but a good one.
Don’t WAIT!!
People here seem to want to take refuge in the timing belt changing rules without seeing the larger picture. Next time buy a car with a timing chain.
You don’t have to do squat. However the risk is you will do $2000-$3000 in severe engine damage if well really when the belt breaks AND have to be towed from wherever you are when dooms day comes.
Call a few independent shops and to get that price down.