In my opinion, and from my experience, unless you're an expert, just have a local wrap shop do the roof for you. It's a big surface, with an awkward antenna and sunroof, that will show any little bubbles. It's especially important to get it applied perfectly due to the extensive sun exposure it'll receive.
A shop won't charge you for extra vinyl if they mess up, but you'll be out $100+ for a mistake.
I've learned to keep my wrap jobs to the smaller projects.
I don't think the roof would be that difficult. It's a relatively easy surface that won't create a lot of warping.
What is most critical however is to have at least two other people working with you. They can stretch the vinyl above the roof has you apply one corner.
Open the sun roof. Start by the front side corner and work in diagonal. Make sure you are well setup with the heat gun and it should be easy.
Just my 2ç