property agent often experience that owner will request alot agent to sell their property for higher price and more chances. however we often feel that property owner would undercut or do not entertain our services. moreover they try to sell their property by themselves just to save money.

What your say ? Should we enforce a law that property owner have to hire a property agent to do the job ?

The problem Sfcc80 worrying is property owner do asking agent sale their house and then undercut agent. This is not about professional services or not.
Ofcause every fields and professional job provided professional service to clients is a must.
As an agent we really dont mind at all for some owner rent or sale his own properties without engaging agent. But if engaging agent and undercut or not paid commission after deal. Thats is too much. Just like visit doctor and cure you illness then not paid, or go for whole and without paid.

We can overcome this problem (undercut )by let owner sign some sort of appoint letter. I myself never use before but i have seen some agencies do apply this.

For "Conman" issue about agents. Every fields do have some rubbish and bad person. That is the image from old tme "broker“ （without going thru agency) and government not yet legalize this job yet. But recent few years properties marketing good and agent do it professional way with engaging agencies with everything by law and finally government legalize its and issue "Negotiator" tag.
That's is some agencies (Cant state the name out) do still have alot of "Conman" agents. Choose some reliable agents to handle or market your properties. Ask friends around sure can get some good agents introduce by your friends.

sad case huh , professional being frame as a conman LOL

My 2 cents on this question: 

Yes an Owner can sell their property without going thru a property agency or RENs. This is a free trade country, and there is no law that mentioned you must go thru a property agency to sell or purchase your property.

The question to the owner is that whether they want to go thru the hassle of initiating the all rounded process or not. 

Secondly yes there are scenario whereby:

1. Agent bring the buyer to the owner property, and happened that owner is still staying there, and at the end of the day owner is dealing directly with the buyer (very rare case but it is still happening, as the owner wanted to save the professional fee that they are paying to the agency) 

2. Another case would be Brokers (so call runners that is brooking the deal with the owner but is not a genuine real estate negotiator) that often tarnish the reputation of an actual Real Estate Negotiator. They represent themselves as real estate negotiators but they are not attached to any realtor and working on their own. People often mistaken brokers as bad agents (but in real fact, they are not agent in anyway) 

Just hire a runner, to do all the paperwork