The best way to deal with Paypal is to have a separate checking account just for Paypal. Then have a savings account attached to the checking. When you get money from Paypal into your checking, transfer it to savings. Now Paypal cant touch it.
Never leave money in your Paypal account that is higher than the amount your state lets you sue for in small claims court.
If Paypal wrongs you and you have proof which you should, sue them.
If you are shipping high priced goods on eBay, put the item and shipping materials on your scale, weigh it and take a picture of the weight then take another picture when the item is sealed with postage stamp and take a picture of that and its weight. Keep a copy of the postage receipt.
Send the item to be signed for.
If Paypal wrongs you, go to your local courthouse and sue the hell out of them. If there is room to sue them for more, do so and the judge might give it to you if you have dotted all your I's and crossed all of your T's.
If you gave Paypal all of this information and they still dinged you the judge may find some reason to give it to you.
If Paypal tries to contact you and talk you out of suing them for arbitration reasons, explain to them that cases are won all the time without arbitration and if they don't immediately, within 24 hours, refund your account and continue to let you use your account without issue, you will sue them. If they threaten you in any way, tell them " to go pound sand".
With all of the above said. Paypal is and continues to be the most used form of payment on eBay and 99% of the time without problems.