Products arriving damaged

So, I feel the need to put this up here cause this has been a frustration lately.

I had someone order a motorhome and several other things.  The motorhome arrived in pieces, with some of the boards of wood literally broken in half.  Like, not like the glue came apart, like somehow 1" wood was completely split.  So, I said send it back, I'd pay for return shipping, and I'd mail them out another one. 

Got it back, repaired, sent back out.  It came in pieces AGAIN.  Now, first off, if I tell you to send something back to me, by all means, don't send it the fastest way possible.  It cost me $20 (what they told me they paid) to ship some pieces of wood back to me.  I sent a completed motorhome, which is a lot bigger than a box made up of pieces, back to them for under $12. 

Also, at some point, I am not liable for your mail carrier's issues.  I have never, and I mean, NEVER, had anything arrive broken moreso than a roof coming off a hidey house.  And I mean, THAT'S IT!  So, a whole motorhome coming apart in the mail, and pieces of 1" wood being literally split in half?  Not completely my fault, or my problem.  I will replace it, if it comes broken the first time.  But if it comes broken the second time, and the wood boards are still split in half?  Guess what, your local mail carrier is just too rough with packages.  It would probably take me jumping on a 1" piece of wood suspended in the air to break it in half.  So I'd LOVE to know how, packaged in a box with bubble wrap and a shitload of peanuts, the boards ended up split in half.  At some point, I can't be responsible.  To protect the products from some of these mail carriers who must decide throwing the boxes off the roof of buildings is the new type of fun, I'd have to package this shit in steel crates -- and imagine what shipping would cost then. 

I will replace things once.  In this case, I spent $20 to ship the pieces back, and yet another $12ish to mail the completed motorhome back.  So I just paid $32 to ship out a $27 product.  Negative profit, wonderful.  If it breaks twice, you're getting a refund, not the product re-made and re-shipped again.  Sorry.  I don't have that much free time to be making three of the same product, mailing three of them out, and making negative $5 on it. 

Not to be mean, but I just don't have that much spare time.  A refund is your friend.