I don't see how those first 3 would cause his symptom (except the battery). The O2 shouldn't affect starting since it is cold and not doing anything at startup. The fuel filter would cause power problems not starting problems. Same for the air filter. Sorry I don't have a good idea of what it is though. I assume this car has no distributor. Assuming multi coils I would guess they all wouldn't fail at the same time. Have you scanned for codes? Is there any difference cold start vs. warm start? Weak battery would be a problem but I would guess he would be reporting slow cranking. Scan for codes.

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra