The fee at KBank when receiving money from abroad via swift is maxed out at 500 baht. The minimum is 200-250 baht, I honestly don't remember the exact amount. There's no receiving fee for transfers via Wise.
Why just KBank and only in Pattaya? You can also try KBank on Jomtien Beach Rd. Just take the baht bus from Pattaya straight to the bank. If you're on a 90 days Non-O based on retirement but staying in another province than Pattaya, you'll have some logistic problems doing 1 year extensions.
When sending large amounts the fee is actually lower compared to small amounts. It's not linear if you understand what I mean. Again,just compare fees.