Air filters

I'm sure I'm not the only one of us to have experienced a problem like this, so maybe someone knows a good solution. We've lived in our current home since the house was built and ever since we've had an issue with our AC. Our filters kept getting messed up and would never stay in place due to a bad design. I sort of gave up on trying to fix it and as a result chin fur and dust has worked its way up through our ducts and plugged up our AC and caused some damage. We got it fixed after the repair guy lightened my wallet quite a bit, so everything is working again and I have a few suggestions already for how to fix the filter issue so that part is all taken care of. Now with all the background out of the way, what type of air filters do you all use? Has anyone else noticed any problems with how fast they fill up with debris? The repair guy suggested to use the cheap flimsy filters and throw them away since there is so much debris being created by my 20 +/- chins which are located only a few feet away from the main return vent. A buddy of mine insists that a washable filter would be better and would only need to be cleaned, and would be cheaper in the long run.