How can someone that has lived for hundreds of years avoid suspicion in the modern world? [closed]

Here are some ideas :

• Certain identity documents (like social security cards or driver's licenses) aren't essential to get by. If you are willing to accept the low-paying work, you will be able to find jobs that look the other way.
• You don't have to live in the United States. While the U.S. and U.K. have a great deal of tracking, the rest of the world does not. In many places, you are who you claim to be. Especially if you can look and sound like a local.
• Some parts of the United States are basically wilderness: Alaska, parts of Hawaii, Texas, New Mexico, upstate New York, even great swaths of Europe. You can be a squatter or homesteader (basically picking a spot and building a home there with no regard as to whether you own the land), and not be bothered by authorities.
• Generational memories are poor. About every thirty years, people will easily accept that your long-lived person is his own son or daughter. Even photographs (which are fairly modern) can be dismissed with a strong family resemblence. If people get too pushy, it's time to move.
• Please avoid the "my long-lived person is rich off compounding interest and good investments". This is just a personal preference because it seems to be used a lot in this genre. Practically: a long-lived person is just as likely to make investment mistakes, or have savings wiped away by disaster as everyone else.
• A long-lived person is going to become very smart. This is usually just reduced to convenient expositionary flashbacks, but I feel it's really not taken advantage of. The long-lived person, depending on how much effort they've put into learning, is almost guaranteed to be both a polymat and polglot. He will probably pick up: farming, ranching, building, electronics, heating and cooling, advanced finance (cash, loans, bonds, stocks (connected to building)), (futures, hedges, commodities (connected to farming)), first aid, chemistry, minerology, forestry, astronomy, literature, art, government (socialism and capitalism both, we vacillate between the two nearly every 60 years), law. What is "basic" knowledge in one generation later becomes "niche" or "rare" or "arcane"; but the person with access to all of the early stuff more clearly can understand the later stuff built on top of it. Likewise, the long-lived person will probably fluently speak whatever languages have come through the region(s) in which he or she had lived, because at some point it becomes convenient to pick it up.
• Mail order (and equivalent) has been around for a while. The person can have access to nice things and remain anonymous.