Seller asked for PayPal fees after the sale. Should I pay them or not?


I recently purchased an item and after accepting my offer the seller asked for PayPal fees (3%). I checked the listing and nothing was listed in the ad about my paying the fees.  I have already payed half the fee but I'm not sure if I should have paid the full amount. Changing the deal after accepting the offer feels wrong to me. Looking for guidance.
fgleason
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In my offers, I always explicitly state it includes ALL fees (shipping, PayPal ...) to avoid confusion.
I always find it interesting that people get bogged down in small details. When we purchased our home I told my wife, if we make an offer $5000.00 less than the sale price the buyer will come back with a counter offer of half that so now we're negotiating over $2500.00. If we offer the ask then that puts us in control. We offered full price and demanded possession at closing, we were in control. There was no further discussion. A paypal fee on a hypothetical $5000.00 deal is $150.00 (which I think is crazy but it's not my company) so you're haggling over $150.00 when spending $5000.00. Doesn't seem like much given the purchase price and certainly isn't worth causing a lot of consternation by either party. I have heard of real estate deals for hundreds of thousands of dollar falling apart over minutia. Doesn't seem worth it to me in the long run. Work it out, make an agreement and don't get bogged down in minutia. Good luck!
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I like PayPal and never ask for the fee's when I sell. I just set the price taking them into account. Shipping depends on item and where shipping to. I would not have paid the fee's but may have agreed to split the difference with the seller if he insisted. It is not that much money.