This could indeed be Cypress, or maybe more likely Juniperus.
I am growing for over ten years bonsai now (with ups and downs), and I certainly don't want to call myself an expert but I think I can share some tips I have learned along the way.
First tip is to find material in your own neighborhood. For example, I live in Amsterdam (Netherlands), and in the ...
Bonsai projects are great! I have many running at the moment too. Also some oak, but mine are branching already... I see a few problems here. First of all, this tree (plant) needs to grow outdoors, not indoors. It needs sun, rain, and wind, but most important cold winters as well. It needs to lose its leaves in winter. Branching occurs very often in spring ...
Value is going to be in the eye of the buyer.
I look at the pot, plant type, age and shape.
The left plant, being so young and not much real shape to it would get no more than a few $ from me.
The right plant, can't quite tell from the base trunk what is going on, but as presented, also not much value there either.