2002 brakes need attention every three weeks?

hi, guys im new here but hope you gm techs can help a ford tech figure out my friends darn cavlier. she has recently taken it to joe blow down the street and he struck out big time. first it all started with a routine maintanance. he found her rotors were out of round and replaced them, good fix there but he didnt look at the back. few weeks later she had rear braking issues and he replaced the drum springs with a kit. and at the same time he noticed her drums were scorned and small cracking had occured. he replaced them and the the lining...then she had a thumping in the rear imediately after leaving the repair shop. she then got fed up and brought the problem to me. found that the new drum on the right rear to be egg shaped and had joe blow replace it under part warranty. well now the thumping is back again. when the brakes are applied, any speed hot cold , including park brake it goes thump thump thump and then the RR grabs and shorlty after the abs kicks in when using the hydrolics. normal for the abs, not normal for all these rear brake issues. or is it common? please help shes old and cant afford to take to gm dealership.

Rear drum issues is quite common with these cars. I've been there, and have to screw around with them myself before i converted to rear disc brake. About to do it to my sunfire as well. Thats how much i hate the ABS and drums on these cars.

Most of the time is from the shoes not being properly adjusted.