Your selections begin with deciding on which styles (or finishes) you prefer. None is "better" than another...it is a personal choice based on the mood and feeling you wish to convey with the portrait. The price difference is determined by the additional handwork involved.
A rich and very durable lacquer glaze is applied to the wall portrait surface for protection and to eliminate the need for glass in front of the photograph.
You will choose which finish you prefer (canvas, fine art, luster) during your image presentation.