While the mechanic was working on my 2003 Toyota echo. He told me my
Rear tires needed replacing. Also the rear tires were wearing unevenly and I
Needed a rear end alignment.

I did not know the rear gets aligned . Does it have the same camber and castor
Adjustments like the front end??

Rear End - Alignment, Measurement - String & Rope - Circle Track (http://www.circletrack.com/techarticles/rear_end_measurement_alignment/index.html)

How many miles were on those rear tires? Were they rotated regularly? Were they kept balanced? You may or may not need four wheel alignment. Number of miles on the vehicle are also a factor. I guess it boils down to whether you have dealt with this shop for a while and have confidence in them or if you should get another opinion, or if the tire wear can be explained by other causes.

while the mechanic was working on my 2003 Toyota echo. he told me my
rear tires needed replacing. also the rear tires were wearing unevenly and I
needed a rear end alignment.

I did not know the rear gets aligned . does it have the same camber and castor
adjustments like the front end????

Any rear suspension will not have caster adjustments. That is a function of the front suspension and is primarily a setting that keeps the vehicle tracking straight when you let go of the wheel on a straight and level road. FYI: Caster also doesn't cause tire wear.

The rear alignment on your Echo isn't done with factory provided adjustments. Any adjustment that are needed would be done by shimming the rear hubs (#6) relative to the rear axle (#7). Some toe and some camber can be corrected by this, but not major changes.



13505

Then again, the alignment may be within spec but more frequent tire rotation may be needed (Read: far less cost and far easier). What are the actual rear supension readings on your Toyota?