Drain troubles

I have always had a little trouble with the drain in my shower. Fairly often (it seems to me) I have to put Liquid Plumber and/or Build-UP Reover down the drain to keep it working. I know this is to some extent unavoidable. Recently, I had trouble with my washer drain clogging up (it's in my garage). I used Liquid Plumber and it seemed to work fine, but about four weeks later it clogged up again. Liquid Plumber solved that problem too. I'm on a tight budget and had recently switched to a cheap laundry detergent. I'm thinking of going back to my old brand and trying it for a while. I am wondering if the cheap brand caused the trouble. The cheap soap is no bargain if I have to buy extra Liquid Plumber. That sgot me wondering if my shower problem is somehow linked to the type of soap we use. Any ideas? Should I be looking into less expensive drain un-cloggers than Liquid Plumber? I'm a stay-at-home mom, so money is tight. Thanks for any advice. Kelley Oklahoma City