Let KAYAK do the searching
Based on KAYAK hotel searches, the most popular destination is Helsinki (84% of total searches to Gulf of Finland). The next most popular destinations are Tallinn (15%) and Espoo (0%). Searches for hotels in Saint Petersburg (0%) are also popular.
KAYAK users have found double rooms in Gulf of Finland for as cheap as $22 (Tallinn) in the last 3 days. The average price is $145.