How can I know if there is a phospholipid (phosphatidylcholine) in a solution?
Your question kind of asks two different things:  

1) Whether there is an easy method to show the presence of hosphatydylcholine
and
2) Whether there is an easy method to show the presence of phospholipids in general.  

My first comment is that if TLC with chloroform is too expensive, then you are probably out of luck. This is not a simple thing to do, particulary the specific analysis of a single particular phospholipid in the presence of others. This Wikipedia article gives some insight on this:  


  There are no simple methods available for analysis of phospholipids
  since the close range of polarity between different phospholipid
  species makes detection difficult. Oil chemists often use
  spectroscopy to determine total Phosphorus abundance and then
  calculate approximate mass of phospholipids based on molecular weight
  of expected fatty acid species. Modern lipid profiling employs more
  absolute methods of analysis, with nuclear magnetic resonance
  spectroscopy (NMR), particularly $\ce{{^{31}P}}$-NMR, while HPLC-ELSD
  provides relative values.  


Unfortunately, these methods are going to be orders of magnitude more expensive to do yourself, as compared to TLC, though outsourcing may or may not be a viable alternative in your case.  

The same article discusses a phospholipid characterization technique based on refractive index measurements that, again, may or may not be a viable type of analysis for your specific use case.