Become acquaintances with the person you want to go have a romantic relationship with. Keep chatting to this person until you hit the Friend level. Speak to them again and go to 'Be Funny...' and tap 'Tell Flirty Joke'. This will kick off the 'Budding Romance'. If you want to take it further and date and then marry , use the options found at 'Be Romantic...'
If you are already 'Good Friends' with said person, and so find it impossible to kickoff a 'Budding Romance', you must speak to the person and select 'Be Rude...' and then choose things like Insult, Humiliate or Argue etc. Continue this until you are dropped back to the 'Friend' stage. From here you can try the above instructions.
For a faster way to 'repair' any damaged electronics, simply go buy any cheap stereo and then repeatedly turn it on and off until it breaks, then repair it. Keep carrying out this set of actions until you obtain the highest repair skill or as long as desired.