In my pre-helmet days I used to wear a Deerstalker hat when cycling. Groups of youths hanging about on street corners would shout out stuff like "whats up Sherlock", which is preferable to the usual treatment.
If you are saving a serious amount of money by cycling, it pays to invest some of that in decent gear. That doesnt mean top of the range "steal me quick" toys, but tough serviceable , good enough components on a nice frame. You need the best tyres you can get, and if you are struggling up hills, then simply customise your gearing. Everyday i see people who could afford a nice bike, struggling on cheap heavy badly geared machines, just making life difficult for themselves.
My own commuting machine was built up from second hand parts for less than £100, but it is perfectly suited to the task.