Standing in front of the Great Pyramids or sailing down the Nile on a traditional felucca is the kind of trip that sticks with you forever. Aim for October through February when the weather cools down enough to actually enjoy walking around Luxor and Aswan without melting.
A typical trip runs about $4500 once you factor in flights, hotels, guides, and internal transit. Spreading that cost out over time makes it much easier to handle.
That intro window is a deadline, not free money. If you still have a balance left when the 18 months are up, standard interest rates will kick in on whatever is left over.