Online Travel Booking and Bidding Agencies - Using PL/HW - date to book?

Ok I am going to book a hotel either using Hotwire or Priceline so here is my situation.

Flying back from Brazil and arrive at 640am into IAD on the 25th and my connecting flight doesn't leave until 5pm. So I was thinking I would get a hotel to sleep/shower for a few hours. Question/Concern is do I book it for the 24th and ask for a late checkout (seeing how I won't even check in until close to 8am) or the 25th and hope they allow me to check in early. Anyone familiar with any hotels in the IAD area that accomodate this issue. Any other suggestions?

Thanks

I would imagine you have a better chance by booking for the prior night and requesting a late check out. Checking in at 700 am is fairly iffy

Priceline requires you to check in by midnight of the date of your reservation so if you have the room booked and plan to show up the next day, you will lose the room. Call a hotel and make a direct booking with one that can accomodate your specific requirements. Skip the opaque sites in this case.