Lightning168,

Most wheel/mag shops accept trade-in.

Popular places to go to are Blumentritt (haven't been there) and Evangelista.

I traded my 16 inchers (several years back) sa DKC Tires sa may P. Tuazon Cubao, I'm just not sure if they are still there, lapit lang sa Ali Mall. So kung malapit ka sa Cubao, you can recon that stretch of P. Tuazon.