Under FOB the seller delivers goods on board and you book and pay ocean freight; under CIF the seller books freight and adds minimal insurance (ICC-C at 110%). In both cases Saudi clearance, duty and VAT are yours. FOB gives you carrier control and tracking ownership — the healthier default.
Beware DDP from sellers without a Saudi entity: they cannot legally be the importer of record, so the promise often unravels at the port.