Hello,   here are a few things I'm seeing.....

 Firstly,  scale and location.  Your model appears to be 100 times Poser scale and it's center is  located far from the center of your 3D universe.  Now, 100 times Poser scale is OK, if you know this and you prefer working at this scale,  ( I work at 10 times Poser scale), however, with the object being so far off center, you're just setting yourself up for extra "trickiness" when it comes time to use the model in a practical sense.

So, in Sketchup, locate the center of it's 3D universe and begin your model or reference from that point. Next, you'll need to understand the scale of your source application (modeler) and your target application (Poser) - this is very important for architecture.

Now, the edges...   For hard surface modeling it's very important to bevel your edges to create fillets or chamfers.

In the 3D universe a single edge is infinitely sharp, in the real world this is physically impossible and in the rendering universe it creates crap-tastic renders when you apply smoothing.  To deal with this you need to bevel your edges.   Here's a primer on Fillets and Chamfers: webservices.alibre.com/OnlineTutorials/Lessons/Learning_Modules/FilletsChamfers/Fillet_and_Chamfer_Primer.htm

I think there are some Sketchup plugins for this, but, you may have to go looking for them.

Anywho,  hard surface modeling can be a lot of fun and there are PLENTY of tutorials out there to help you.

One last thing,  if you're serious about this, consider Wings3D - it's very powerful and it can really help you develop good 3D discipline.

take care
Joe