In Portugal, the buyer is liable to pay all of the purchase costs, including notary fees, stamp duty, land registry fees and transfer taxes. The vendor is liable for all ownership costs in connection with the property up to the completion date. The agency fees are paid by the seller, if not mentioned otherwise.
Exact costs will vary by region, by value and type of property. However, usually you should allow 10 to 15% on top of the purchase price to cover additional buying costs. (see detailed costs below)

Legal fees
Notary fees: Please allow for approximately 0.8 % for notary fees, 0.8 % for stamp duty (Imposto de selo) and 150 EUR for property registration costs.
Other legal fees: UK and Portuguese legal costs will usually come to around 1 to 2% plus VAT/IVA/MwSt.

Other buying costs
Mortgage arrangement fee: The mortgage arrangement fee to your lender will be around 1.5 to 2% of the value of the loan.
Survey: If you decide to have a survey this must also be factored in and will come to around 0.5 to 1.5% of the purchase price. Buyers may also have to pay their first year of rates on purchase.