There are various meta search engines like momondo, kayak and skyscanner which aggregate flight costs from multiple airlines and send email notifications every time there is a price fluctuation. Take 2-3 weeks to understand the trend and make a booking when you feel confident about the pricing.
2: Accommodation (385 Euros)
The cheapest (almost free) mode of accommodation is couch surfing. It involves reaching out to the locals (online) and requesting them to host you for the duration of your stay, sort of like a cultural exchange.
Go to the couch surfing portal, create a profile and request locals to host you. There is only goodwill exchanged in this dealing,money doesn't change hands. It is only good manners to take a gift, cook a meal (mind the spices) or teach a skill in order to show appreciation towards your hosts.
If you fancy sharing a bunker bed with travellers from different parts of the globe then youth hostels are right up your ally. There is an extensive network of budget hostels spread across Europe where you can crash at night and meet backpackers and budget travellers alike. Booking, hostelz and Hostel booking are portals with readily available information on hostels.
Bed & Breakfast