Well , we have been doing the above , and the profit margin is quite small.
Yes you will have to pay revenue .
You may have to produce an invoice to Customs , before the goods are released and then goods are valued by Customs .
In my case I receive an invoice from the courier and they normally charge the following :
1. VAT on items
2. Administration Fee
3. VAT on Administration Fee
An item may seem cheap in China / USA , however after you add on the shipping charges + the above charges , you will find that the item from these foreign lands are not as cheap as you expected them to be .
You will also find that most of the items on sale are either generic or original brand name fakes .
I have seen an item on sale on eBay for €65 , that costs me € 90 . You will find that some eBay sellers drop-ship directly to the customer and it is only afterwards that the buyer receives the invoice from courier for vat etc .( hidden costs )