Hi if you have a residents visa I believe you do not need an entry visa if you leave Egypt and return within the validity of your residence permit or within six months, whichever period is less.
If you are an investor you, your spouse and children can apply for 5 yr renewable residents visas - cost is about 200le.
You can find more info here
http://www.moiegypt.gov.eg/English/D...eb/residence5/
You should get cheaper hotel rates and flights with Egyptair but I dont think there is much difference in the flight prices any more. You can also get cheaper fares for the ferry as well.