Depending on how good you are on the thing you're applying for you can get jobs as much as $60/hour (only tested upwork). You also have to apply some country filtering, don't hope to get paid $30/hour by some Pakistan company. Higher than that is really difficult.

But there is other coin too, once tried to hire some `solr` experts ($100/hour rate) whom after I asked about some extension development went out of touch (1 agency & 2 contractors). So it can suck on client side too.