Lockdown is lifting, and with thousands of companies operating remotely through Labor Day and summer camps largely canceled across the country this year, many travelers—families, couples and anyone who has been cooped up at home for months with no place to go—are still seeking a summer getaway. Coronavirus travel safety questions may make a week or two in Europe or at a far-flung beach resort unlikely this summer, but one option we’re seeing right now: extended-stay bookings in destinations clos...