What watt RHP should I put in PVC?

[Aurora Borealis]

Hello!

I'm planning on buying a pvc for my lovely 2014 female Kahl sunglow. What watt heat panel should i purchase ? The room is heated with baseboard heaters, if that makes any difference.
Also I am planning to get a herpstat with it. I've never had heat probes going into the terrarium. Where to put it and how to keep it secured ? I know tape is a no no, and I want to make sure everything is safe and easy to clean.
Lastly, if I'm getting a heat panel, what height should the pvc terra be ? Would 4x2x16 be comfortable for a non breeding adult female bci ?

Thanks