Let KAYAK do the searching
Based on KAYAK hotel searches, the most popular destination is Cascais (74% of total searches to Costa do Estoril). The next most popular destinations are Estoril (15%) and Oeiras (8%). Searches for hotels in Carcavelos (3%) are also popular.
KAYAK users have found double rooms in Costa do Estoril for as cheap as $89 (São Domingos de Rana) in the last 3 days. The average price is $146.