The TARDIS, duh!
Why? Because it’s a time-traveling spaceship! Is any other reason needed? Oh, yeah, one other reason: it’s far bigger on the inside than on the outside.
So I could load ALL of my belongings into it, hop over to the UK, and move right on in. Live there for years, even decades, and return to the States (after all, I’d have to visit my family) five minutes ago. Not to mention visiting other planets; visiting other places on our own planet; or getting to talk to deceased people I admire, like Shakespeare, Milton Erickson, etc.
And no worries about affording the cost of living anywhere. I can either just live in the TARDIS itself, or go back in time a century or so, deposit a miniscule amount in a decent interest-earning account, and hop forward to collect my earnings.
ETA: Oh, forgot the most important reason: All that travel, with NO TSA!
