NEVER answer a call that has the exchange prefix starting with "0" or "1". So, although 210 is a valid area code for Texas, real phone numbers require the exchange (the next three digits beyond the area code) to start with 2-9 in the North American Numbering Plan Administration area (NANPA) which is the U.S. and Canada. So, 210-123-xxxx, 512-098-xxxx, 972-145-xxxx, even 888-188-xxxx, are ALL spoofed. (also 123-4567???... come on!)
If they have to resort to faking their phone number, you do NOT want to do business with them. They're crooks! And these crooks are stupid just like a lot of other crooks: bank robbers who write their holdup notes on the back of their own, personal deposit slips; fugitives who get pulled over because they commit dumb traffic violations or who just don't bother registering their cars; shoplifters who walk out wearing stolen merchandise with the tags still showing.