The first step that you can take to protect yourself from scammers is to go to your eBay account in My eBay and change your eBay Preferences. Change the Notification Delivery of all messages from HTML to Text-Only format. This way, when you receive messages from eBay to your registered email address you will know immediately if you are receiving a fake invoice, phish or a spoof message, because if those messages arrive in HTML format, you will know immediately that they are phony.
Second, change your Buying Notifications to NOT subscribe to Second Chance Offers. If you refuse to receive Second Chance Offers then you should NOT receive them. After changing your Preferences, if Second Chance Offers do arrive addressed to your registered email address you will know that they are phony.
Third, whenever you receive an email from eBay, double-check and make sure that it is in your My Messages in box in My eBay. If the message you receive to your registered email address is NOT in My Messages, then the message you received is phony.
Fourth, while you're making changes to your eBay account go to your PayPal account and change your Preferences to ONLY receive messages in Text-Only format. Then afterwards if you receive email messages from PayPal and they are in HTML format, you will know immediately that they are phony.
Change your Preferences and take these simple precautions and you will be taking a step in the right direction to protect yourself from scammers.