Still life
 

Please rate the level of the artist, if possible on this photo.

The work is not professional,most likely a copy .Identification of variant.

To estimate the size of the photo is the back side ,preferably macro painting.
This may be a copy,reproduction,printing, etc.- anything.This photo definitely say it is simply impossible.But if it's art ,then record it in the "non-professional" means a sign of incompetence .

Size sm.
Oil on cardboard.
This is the work of my good friend.

Amateur with an artistic bias....

[QUOTE=west;3419581]Size sm.
Oil on cardboard.
This is the work of my good znajomego@

Your friend develops akaichou technique commercial still life. This technique was common ~ 200-300 years ago.
Bright representative of this line commercial painting:

Jan van Huysum

http://www.posterclub.ru/author/?an=Jan+van+Huysum

Elements of this technique beginners learn about a couple of quarters before identification of the level of sales.

But your friend have significantly less embellishment than is required for rapid and successful sales.