I bought 12 WORST Inspiron 3567 from ebay

Dell does not sell on Ebay. You bought used, damaged and/or broken computers from private sellers. They could have been sold for parts. Complain to Ebay and the sellers. You probably would waste money on trying to fix them. Laptops usually get replaced not fixed. Parts can be expensive and hard to find. 

Assuming that you didn't pay too much for the lot, you can switch out parts and get some of the laptops in working condition again. Just use the parts that work and are in overall good cosmetic condition.

To add to my above post...

Inspiron 3567 Service manual

Some suggestions:

• Second laptop - Assuming that the keyboard isn't damaged, it may simply need its cable re-seated to the motherboard. Test the keyboard with another system if it's still not operational.
• Seventh laptop - 8 beeps = LCD failure. Maybe solved by re-seating the display connector on both the motherboard and on the back of the display panel.
• Ninth laptop - CMOS battery is likely dead and will need to be replaced. Try using a CMOS battery from another system, reset date & time and see if the error goes away.
• Tenth laptop - Reinstall Windows with an external monitor. If system is still slow, it may point to a failing hard drive. Try using a drive from another system to confirm.
• Eleventh laptop - Try reinstalling Windows. If BSODs still persist, re-insert memory modules, hard drive & WiFi adapter. Run Dell Diagnostics and run an extended test to thoroughly check all components. Switch these parts if needed with another system to rule out faulty hardware.