Hi Joanna,
You're in the right place for friendly and expert advice.
From me it will be just friendly, as I am still in the early stages of building my 5x4 knowledge.
One thing is can chip in is to consider what type/s of 5x4 photography you think you would enjoy most.
I have used an Intrepid and think that as a field camera the light weight would be helpful, but the crude movements and (in my opinion) flimsy construction put me off.
For architecture cameras with good strong (geared sometime?) rise, fall, shift and tilt should be prioritised - others can make suggestions if you indicate that is a priority.
Finally a good friend has a monorail Sinar camera because he does mostly still life, and is content that the camera is not ideal for landscape or portraits, which he also creates.
Personally I use an MPP which was a bit of an all round camera, bit heavy but strong.
Hope you ask lots of questions before you buy as a camera that puts your back out or otherwise blocks your workflow will add another problem to your learning.
Robert