Here are the homemade and the store bought polyester peplum jackets side by side at the point at which I began the stuff that can cause the homemade one to look too homemade to wear: the collar, the facings, the topstitching, and so forth.
At that point I measured all the parts of the RTW jacket, which is right now just a little roomy on me, and made sure that the homemade one matched.
The RTW has pleats while the homemade has gathers and the RTW has lapels and fastenings while the homemade one has a straight front and a stand-up collar. This reassured me a bit: the homemade one is clearly easier than the RTW.
I went ahead and added the collar, did all the interfacing bits, sewed on the facings, pinned it all together, and tried it on. It’s not that bad. Now I just need to do the finishing, every moment of which brings up the possibility of making the jacket completely unwearable.
But it hasn’t happened yet.
I completed the top, the skirt just needs hemming, and the jacket is well on its way to jacketicity. Not bad for a Labor Day weekend.