my dog eats weird things.

S
My little 7 pound yorkiee poo is quite a character.  He's lovable, but a little jerk and weird, but adorable.    He's always eaten weird shit around the house.  Usually chewing on something shiny, that lil gangsta.. 
Lately it's been hairties and zippers coins and nbracelets.    I've had to buy bulk packs of hair ties because they always get chewed up.  MOST of the time I find shredded ones around the house but once I found one in his poop.  😓😫😖.  He's also been into zippers lately as well.  Those are his two favorites but he loves chewing no edible stuff and I wonder what fragments make it into, is stuck in. Or has gone through his digestive tract.  Today I found a broken, brittle pen cap.   I hope he didn't swallow any fragments.  He goes pottybin the house on a pad And I can monitor his poop closely and besides that one hair tie I haven't found anything forigne yet, thank god.  .  .  I fear what might be stuck inside.   We have a hard floor so we can see things easily and I sweep daily andbillnpicknup anything I see but there's still so many hiding spots he could keep stuff.  
We can't afford an X-ray or a surgery if god forbids, he does need one.  He doesn't seem in distress or pain. I'd take him in to the vet if i thought he was suffering.  If he does need something major I might have to sell a kidney or something... idk.