First Yoann the build is going along nicely.Not much of a painter myself but I can give a couple of tips that seemed to have helped me in the past.First wash the model with dishsoap and warm water.Then shoot it with some primer and then wetsand the primer.It give the paint something to grab a hold of and stick better.Some sand before the primer.Myself I have tried and didn't see the differance.
BTW,never throw a model in the trash.You can always save parts fer a future build
Keep on building.That's the only way to get better.
It's a re issue.I'ld been wanting one ever since I got back into building models several years back.But like you said,I could buy a used car for what they were going for on ebay.I was thrilled when they re released it. I plan on getting another so someday when my skills have advanced I can build one that's heavily weathered.