Depends what spec the engine is built to, the parts are by far the biggest cost. As an example; on this engine build the 2.4 pistons and rods cost £1500
Compcams are now over £750 delivered (they used to be £480), this is because the exchange rate is currently quite poor, plus import duties.
As a rough guide £3000 - £4000 for a fully rebuilt z22se engine = new chains kits, crank bearings, water pump, rebore, dbilas valve springs, wiseco pistons, eagle steel rods, rear main oil seal, oil pump gasket, head gasket, head bolts, valve stem oil seals, open up exhaust ports, balancer delete, gapping the piston rings, etc