Let KAYAK do the searching
Based on KAYAK hotel searches, the most popular destination is Siófok (50% of total searches to Lake Balaton). The next most popular destinations are Keszthely (33%) and Balatonfüred (17%).
KAYAK users have found double rooms in Lake Balaton for as cheap as $52 (Siófok) in the last 3 days. The average price is $232.