My partner and I went on the 2 hour bike tour with Lucy who was very knowledgable and gave us a great tour around Sofia. This is a fantastic introduction to Sofia and the guides are happy to help you out with any other questions such as recommendations for dinner, or other places to visit in Bulgaria.
The next day we completed the hiking tour in Sofia. We caught a cab which our guide organised (9 leva for one way trip) and began our walk up the mountain. It is a steep climb and you do need to have a good level of fitness to complete this-it is quite steep and rocky so good footwear is essential. Our guide was helpful and friendly and the Boyana waterfall at the top was stunning. After our descent down we visited the Boyana church which was great-you do feel very tired after the trek but the church is worth it (and free after 3pm on a Monday, otherwise 2 leva entrance fee). Overall, all guides were passionate and knowledgable about their city and their was no pressure for tipping-however they do such a good job and are giving up their time this is essential to do. I recommend both of these tours as they gave my partner and I a great feel for Sofia and we really enjoyed them both.