Crowdsourcing is an assignment model where multiple translators can accept a job and work together on it, rather than assigning a single job to a single translator. Crowdsourcing works best when you have a team of translators you trust. Though not appropriate for all projects, at its best, it allows you to turnaround some kinds of projects faster and with significant cost-savings. Cost-calculations are not done automatically in crowd projects, so you’ll have to define your terms with linguists separately. For projects paid-by-the-hour, like post-editing often is, there is no special complication for cost calculations.