I'll toss something out that might be helpful.........
Were this my van and suffering with the poor paint adhesion especially on the lower areas I'd strongly consider something like Monstaliner, similar to the Line-X products but seemingly a bit more user-customizable and applied via roller or brush to great effect. It can be tinted to match or contrast with existing body color quite easily.
http://www.monstaliner.com/
Removal of masking tape can be made infinitely easier with this product:
http://www.langeman.com/WireTrim
If the existing body paint is acceptable this approach may be more budget friendly, easily done DIY and at least partially addresses the adhesion and appearance issue.
Something to consider, another way to go perhaps.