Just some observations - public transport is poor in Sofia. However, taxis are very cheap and plentiful. I have never had a problem, but of course there are stories of cabbies trying it on. Normal caution should suffice.
Pavements are dreadfully dilapidated, and often obstructed by parked cars. This is not a town for baby buggies, let alone wheelchairs (I have never seen anyone in a wheelchair). The elderly should also beware.
A good guide, published quarterly is Sofia in Your Pocket: www.inyourpocket.com
Also, an English-langauge newspaper Sofia Echo, published Fridays with listings: www.sofiaecho.com
In August, theatres are closed, and some restaurants. Check first.
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