Work out the margin and markup on a price, or the selling price you need for a target margin.
Margin and markup aren’t the same thing. Margin is profit as a share of the selling price; markup is profit as a share of the cost. A product that costs 60 and sells for 100 has a 40% margin and a 66.7% markup.
To price for a target margin, divide the cost by (1 − margin): for 40%, 60 / 0.6 = 100.
Margin = (price − cost) / price Markup = (price − cost) / cost Price = cost / (1 − margin)
Because the cost would have to be zero. Markup, on the other hand, can be 200% or more.
Without. VAT isn’t yours: you collect it and pass it on to the tax authority.