Buyers often don't know an eCheque has been spawned, so I usually send them a message letting them know, and also that the item won't be posted until payment is cleared.
Unless there is money in my PayPal, my purchases are usually paid from the bank account. Most of the time they go through as instant payment, but every now and then it will show that if I proceed, the payment will be an eCheque and the item won't be sent until it's cleared. If I'm not in a hurry for the item I will let it go through. If I am, I'll change the payment method to the credit card.
It's in red, but the writing is small, so some buyers may not see it. Others may not even know what it is, so proceed anyway. Most of the time they take 3-5 days to clear, but I have had them take 2 weeks. When they take longer than normal I will send the buyer a message letting them know payment still hasn't cleared.
From the buyers end, instead of having the blue $ showing as payment made, there will be an egg timer. The same thing will be seen on your selling page next to the item. When the payment clears, it will change to the $ sign. PayPal will also send you a message.
