If it is too warm in the flat overlooking the Nile, maybe an evening at the bungalow near the pyramids would be better, unless he can spring loose for a weekend at the summer place on the Mediterranean near Alexandria.

He can leave his late-model Chevrolet in Cairo because his wife likes to have her red Toyota when she stays over in Alexandria. And if 17-year-old Ashraf can take time away from his university studies, he can drive down in his Fiat and bring his sister Hoda.

Business is good these days for Halim Khalil, who has used hard work, President Anwar Sadat's open-door economy and the Carter administration's massive aid program to turn his wire and fence factory into a million-pound-a-year (about $1.4 million) operation employing 80 persons and making a healthy profit.

"It is the best way," he says of Sadat's effort to shift Egypt out of heavy-handed state enterprise into more free-market business. "Before, everything was separated from all the other countries. Now, you can sell everywhere, even to the Jewish people."

The campaign still has a long way to go. Egyptian officials estimate 90 percent of their industry remains in government control. But the result of loosened restrictions and the new attitude toward private enterprise can easily been seen.

Cairo's Shawarbi Pasha Street resembles a consumer goods fair. Shops and curbside stalls sell French perfume, stylish clothes, American kitchenware and a startling range of Japanese televisions and appliances.

The sight of these signs of wealth seems to play an important role in the widespread conviction among Egyptians that peace with Israel and friendship with the United States will ease their poverty after the decades of war and deprivation under the late president Gamal Abdul Nasser. Even Egyptians who cannot afford to buy appear to take pleasure in strolls among the new goods for sale.

Moreover, a tiny but increasing number of Egyptians can afford to buy. There is no official count but estimates place the number of new Egyptian millionaires at 500. Hundreds more are getting wealthy on a lesser scale.

A major turning point for Khalil was a $1.25 million loan from the Development Industrial Bank two years ago that enabled him to expand and remodel his factory with British and West German equipment. The loan was granted under a program to stimulate private enterprise funded with a $31.5 million credit from the U.S. Agency for International Development. a

"My performance is up to the same standard as foreign production," he said in an interview. "I am now using the latest machines. We hope to be able to export soon to the Arab countries, or perhaps even Israel."

As a result of the expansion, Khalil estimates his 1979 sales will add up to about a million Egyptian pounds, or $1.4 million. By the end of 1981, he has plans for three times that much in sales.

"I work from eight in the morning until the middle of the night," he said. "Sometimes I am so tired I forget my own name."

The work also brings its rewards, however. Khalil's wife and their two teen-age children spend two summer months in the apartment at Maamourah, a fashionable Alexandria suburb where Sadat also spends the warm days of summer.

Ashraf, the son, attends Cairo University, where he studies accounting, as did his father. Hoda, 16, the daughter, attends a private English high school that costs about $1,400 a year.

"I think my son will come to work with me after university," Khalil says, clearly looking forward to it. "And my daughter also, if she doesn't marry early."

Khalil, 49, travels to Asia and Europe three times a year for business contacts. He is looking forward to a reconciliation between Egypt and the other Arab countries in the hope he also will be able to do more business in the wealthy Persian Gulf oil countries.

Egyptian business now is hindered in these lucrative markets by the boycott established by Arab countries to protest Sadat's peace with Israel. In the end it is the uncertainty of such politics that is the main cause for the worry to Khalil.

"Things are good now, under Sadat," he said. "But what would it be like if he went, or it something happened to him? We don't know."