Egypt is remarkably affordable for travelers. Budget travelers can live well on $25-40/day outside of tours: koshary for $1, guesthouses for $10-20, and local Cairo metro trips for pennies. However, the must-see attractions add up quickly: Giza entry is $20, the Egyptian Museum $15, Luxor sites $10-25 each.
A practical middle ground is to budget $60-100/day combining local food and accommodation with paid site entries and a private driver/guide. Nile cruises (Luxor to Aswan, 4 nights) start at $300-400 per person including all meals and site entries — excellent value for what's included. Bargaining is expected at souks and for taxis, but agree on the price before getting in.