Sofia - SOF has the most flights:

Driving non-stop to one of the Villas from Sofia Airport will take you 4 Hrs & 30 mins

You have 3 options to get to the Villa:

Rent a Car - this gives you the most flexibility & if done in a timely manner can be quite affordable.

                A standard fuel powered car will get you there easily (charging stations are still rare sightings in the mountains)

                However if you really want to explore we recommend a 4 wheel drive with good ground clearance.                          

Get Picked You - We can arrange a pick up (This obviously is the easiest but the most expensive approx 150e one way)

Bus takes about 6 Hrs but only run a few times per day but if you not in a rush it's less than 20e one way

My favourite way to arrive is break the journey with a stop at Villa Ustina a highly rated reasonably priced vineyard;

Take tour, have some food & enjoy the winery & stock up on your favourites for the visit

Then continue on to the houses ... if you can still drive!

This airport is smaller, less used but nearer to the houses

... the drive is about 2 Hrs less about 90e for a pick up

But again a car rental is recommend to give you mobility during your stay