Set a cap on my shipping charges when buyers purchase multiple items

[mametsu]

So i sell mainly trading cards and charge shipping on my items. Most fall into the ebay standard envelope and i charge the .69 cents. I run promotions and frequently get buys of 4 items and i typically then ship usps which costs like 4.50. Ive run into a few buyers wanting much more cards and always just refunded the excess shipping they end up paying. My question is, is there a way to set a cap on the shipping charged? Say someone buys 20 cards under 20 dollars, instead of being charged 13.80 for shipping could i run a cap at 5 so they only get a 5 dollar charge? I fell like i would get more bulk buyers this way even though i do always refund the shipping difference if they pay more. Any ways to do this or advice is much appreciated! I didnt want to run free shipping and bake the cost in though i am considering it now.

[whitewaterford]

@mametsu I've never done this, but go to your combined shipping options (https://www.ebay.com/ship/prf/combinedshipping?&education=false)

Then try a promotional shipping rule and see if you can find something appropriate:

[ittybitnot]

@mametsu 

I would explore the 'combined' shipping rules as provided to you in message #2.   Something that may interfere with that is your "Buyer Rules" require auto-pay for offers.  Though you do not use auctions at this point, the settings prohibit combined shipping, as each offer you accept will be auto-billed immediately and separately at full shipping cost which sort of defeats the purpose of what you are trying to accomplish.  

You can view them here: 

https://www.ebay.com/bmgt/buyerrequirements

Buyer Rules:

*Require buyers to provide a payment method before they place a bid.

*Require buyers to provide a payment method before they make an offer.

Click submit or save.

You may have to turn these off to prevent the auto-pay feature from taking over or dispense with the BEST OFFER feature.  Though eBay says turning them off may result in more non-paying buyers, BUT they don't tell you that turning them off may result in more buyers that DO pay and would like to combine items for one shipping price which becomes a simple matter once again.