Hello fellow Fodorites,
I will be in Sofia just for 24 hours on Dec the 3rd staying at a hotel at the airport.
Upon my arrival around 10 am, I will need a transfer from the Airport to the city centre and back.
I only want to use a private vehicle or a taxi. Anyone has used a private transfer and can recommend a reliable inexpensive company ?
Can I just take a taxi from the line at the Airport without the risk of being overcharged ? This happened to me during a previous visit to Sofia, and ended up with a taxi driver yelling at me in Bulgarian,
which was very unpleasant.
Thank you in advance for your help

"I only want to use a private vehicle or a taxi."

Why is that?

You could simply take the metro(subway) for less than 2 leva, with no overcharging and no one yelling at you.

https://www.metrosofia.com/en/

I normally would have taken the metro but I have a wounded leg and can't drag my suitcase through the streets of Sofia.
A cab or private transfer is therefore my only option.

I only used the metro so I can't give you personal advice on taxis and transfers other than googling it, which you can do yourself.

If you end up taking a taxi you could try to agree on a fixed price with the driver before you get into the car and write down the registration plate and try to keep all your luggage next to yourself(not putting it in the trunk, so the driver can't ran away with your stuff in case he's upset for not being able to con you).

Thank you BDKR, dealing with almost the same problem in my own city, Athens... I always use an App on my smartphone and that had always worked very well.
I phoned the hotel to get more information on how to co ordinate my check in with the need to be in the city later on and was happy to find out that there is a similar App
in Sofia too with the name TaxiMe, which is absolutely reliable and offers an honest service. I already installed it on my phone and will be using it once in Sofia.
I am sure this App will be helpful to others visiting Sofia too and having the same questions as I did.

At the airport there is a taxi office - go there and they will sort out a taxi for you. Don't hail a taxi yourself as there are scammers!
I have helpful info here:
http://gruntiestravels.com/sofia/

oops, just seen that i posted this too late!
oh well, maybe this may help someone else