questions about repainting

i have a couple of questions for repainting, i want to repaint my classics optimus prime since the paint scratchs reaaally easily so here we go"
1.Do you have to take all the pieces of the toy to repaint it?
2.How do you blackwash toys?
3.Any tips for begginers?
4.Whats the average time that takes to repaint toys?
5.What type of paint do you need to buy?
thats all...hope you can help me.
thanks in advance
1.Do you have to take all the pieces of the toy to repaint it?
2.How do you blackwash toys?
3.Any tips for begginers?
4.Whats the average time that takes to repaint toys?
5.What type of paint do you need to buy?
thats all...hope you can help me.
thanks in advance