<p>Okay, I grew up in Phila, lived in the Boston area for 20 years, then moved to Seattle.</p>
<p>1) you can rent in Phila and return the car in Boston. If you're not limiting yourself to cities (and maybe even if you are), this is the best option.
2) BUT be aware the drivers on the east coast are not nice. Unlike Seattle drivers, they don't think other drivers should be on the road too. Take the worst, rudest game-night traffic and imagine yourself driving in that all week. If you're okay with that, driving will be fine.
3) The trains out to Swarthmore and Haverford no longer run frequently. They are a pain in the rear, honestly. (And I grew up in the area, love trains, ride them whenever possible.) (And if you're considering Swat, you really should look at Haverford and Bryn Mawr too while you're in the area.)
4) The train from Phila to Boston is okay, but time consuming. </p>
<p>SO here's my take on it:</p>
<p>Fly into Phila; have your D take the train from Princeton and meet you there. (You don't need to see it if she's been there for weeks. Really. It won't change her opinion, and your opinion doesn't matter.)
Spend a day visiting Swat, Haverford, Bryn Mawr. Consider making it two days and seeing Penn too (you've got most of the rest of the Ivy League, why not?).
Drive to Columbia viciniity in the evening (or at least northern NJ, if you want to save money), visit the next day, and continue on to New Haven. (I would spend a half-day at Columbia, but then, my daughter and I did a lot of two-a-day visits.) See Yale. Consider going on to Brown (see two-a-day?). See Olin. </p>
<p>Then give up the car when you get to Boston. It will cost you about $25/day to park, and you really don't need it. Stay in Cambridge, see Cambridge, and fly out of Boston. It may not even cost you extra to take the car one-way. Call and check with the big car rental agencies. I've done it for free with Hertz.</p>
<p>Etc. You CAN see MIT and Harvard on the same day--they are very close geographically--but IMHO Cambridge itself merits a few days. See the Glass Flowers at Harvard; see the MIT Museum, etc. </p>
<p>No one has pointed out that summers are a terrible time to see colleges. You can see the facilities, but the students who make it what it truly is will be gone.</p>