Hi- I'm trying to update my porch to create more of a clean/square look. My plan was to use 1x6 across the top underneath the soffit. Then wrap underneath and on the back part (if that makes sense?) I was then going to box out the columns with 2 1x8's and 2 1x6's.

My question/problem is on the back side or underneath the porch is much higher then the front. Currently the trim piece under the soffit is 3.5" (photo 2 & 5) and under the porch side is 10" (photo 1, 3 & 4). How should I go about doing this? Do I need to get a 1x12 and rip it to cover all the way up under the porch? I was trying to avoid that because the porch is 32 feet long. So that would add a significant amount more $. Does anyone have any other ideas on this? Maybe I'm going about this wrong? Currently everything is wrapped in trim coil.

Also, what type of material would you recommend for this? Most of the columns and header are protected from the weather. Except for the two columns on the corners. I was thinking about doing some kind of PVC trim for the whole thing. I't more expensive, but it seems like it's easier then doing wood. Would last indefinitely. Then only drawback I can see from using PVC trim is it expands and contracts a decent amount. Espcially in runs over 8 ft. I would be worried about the 32 ft I would have to cover on the front and back. Should I cut 2 16 ft pieces and scraf joint it together? Or would you cut it into 3 8 ft pieced and use a scarf joint?

My ultimate goal was to make this as easy as possible because I have a lot of projects I want to do around the house and I don't want this to turn into a major overhaul. I thought about taking down the trim coil to see what I'm working with, but I'm hesitant to do that.

Thank you!