Value derives from value systems. Everyone has values. In determining price one must present an idea, a service, a product or other commodity to a known value system from the perspective that buying the item presented, or acceptance of shared ideal will furthering that specific set of values.
Everything has a price - if only the time involved in listening to a presentation, reading an advertisement, engaging in a conversation or attending a meeting. Some of my friends volunteer their assistance to many in the small business realm. It is an investment in the future of this country they value .... and it takes an investment in time on the part of the companies they advise to absorb their guidance and decide whether or not to use it.
Another way to favorably present the item, issue, belief or service is that not buying or accepting the belief will threaten that specific set of values.
Whether selling, preaching, philosophizing, teaching, counseling or mentoring if you find ways to threaten or further your target audience value system they will act.
There are a lot of answers on this question. I would like to just say simply:
Value is [what a company gives to its customers and/or adds on top of existing products] minus [what the customer has to give up or pay to have it].
It is based on actual or perceived value gained.
There are multiple methods of generating value for your customers. From offering more supply output demands (ex. bulk-breaking or offering spatial convenience) to taking on more flows (ex. inventorying or information).
What type of value, and how much of it, depends on the cost borne by the company, as well as the importance of the purchase and/or partnership.
Value is a relative measure. Value comes from being able to supply what is demanded from someone. It is a proposition that satisfies a need. It is a function of demand, supply, perspective, intention & above all integrity & empathy.
Value is a perception of worth. Perceptions change with context.
Give more than you get and you will generally be perceived as valuable.