The opening scenario is so vague but lets give it a stab,
Let me get this, a client asks you to design and make a 'plush toy' wit ha quantity of 1000. You want to sell it to the client for £7.98, presumably plus VAT.
You want to buy it from China for £2.16 plus shipping, plus duty, plus import fees, plus VAT, and if it's classed as a toy it must conform to a variety of regulations. Air freight is about £14 per kilo, sea freight takes time and is cheaper. Lets say 1 piece weighs 100 grammes, that's £1.40 for shipping. Lets assume all the other stuff adds another £1.50, so total 'IN 'price to you is, say £5.00. Which means 5x 60% + = selling price £8. This is 37.5% GP or £3.00 per piece, or £3000 for 1000 pieces.
The client wants a sample before placing the order, you want a 50% deposit with order, client wants 90 days, no deposit, what are you going to do?
I know what I would do.