One more suggestion based on service of Turkish Airlines this time to North America. Based on their service you may book cheap open jaw flights to sunny California. Open jaw tickets to San Francisco are available already for €166 / £143 when departing from main airports in Italy and returning vack to Vilnius or Tallin. Again due to this is possible error fare do not book your connection flight nor accommodation in US before you receive formal confirmation. (even after that we recommend to wait few days before taking any further action..)
As in previous cases with Turkish Airlines you may find the lowest fares in May and June 2016. You may refer to below booking sample to California further we remind another great deals based on similar routing this time to South America - either Argentina or Brazil..
Booking samples
Travel date samples
8. - 23.5.
22.5. - 6.6.
30.5. - 7.6.
6. - 27.6.
We recommend to check your connection possibilities through service of Skyscanner. This tool gives you quickly a rough idea which low-cost airlines are connecting your home town. To book your accommodation in California you may use Booking.com or consider following promo codes offred by Otel.com, Hotelopia or Venere.
Booking sample of cheap open jaw flights from Europe to San Francisco from €166 here. In this case you would fly from Milan to California on 23rd of May 2016. You would return from USA back to Vilnius on 6th of June 2016.