Where should I park in the main tourist areas of Philadelphia? Are there reasonable parking garages? Any tips/places to avoid? Also, can you recommend a reasonably priced (less expensive, but clean, under $100 if possible) hotel either in the city or close to a metro line outside the city so that we can get settled and drive/metro in? What do you suggest?
Pretty much all garages are less than $30 per day. There are several public garages near (within 2 blocks) the National Constitution Center and The Liberty Bell. One option if you plan to spend the day traversing the city, you may want to consider purchasing a SEPTA liberty pass for $11 and that will give you access to all forms of transportation (bus, subway, trolley, regional rail) starting at 9am.
Btw, you might be able to use hotels.com or priceline to get last minute deals but I would be wary in the city for any room under $100. I good bet is around $150.
Septa has a family pass for $29 and good for up to five family members versus the current $12 per person for the individual independence pass: http://www.septa.org/fares/pass/independence.html. This might be a better option depending on how many are in your traveling party.
Four Points by Sheraton is a reasonably priced hotel near the airport that I stayed in a few years ago. It's close to the regional rail train that goes directly into the city center (SEPTA Suburban Station near restaurants and shops and SEPTA Market East Station near the main tourist attractions). The hotel might have an airport shuttle which you can take to get you to the train or the shuttle might drop you off at the SEPTA: Eastwick Station which is closer to the hotel.
As mentioned above check hotels.com, priceline.com, and travelocity.com for deals. You should also check out groupon.com and livingsocial.com to see what getaways they have available. They may have a package for center city philadelphia.
For parking you can check out http://philadelphia.bestparking.com/
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