I know this is a pretty broad question because slavery has been common at different points in time and all over the globe, but I would be interested to hear responses about any era or place.
I know, for example, that one of the main arguments against abolishing slavery in French colonies (like Saint-Domingue/Haiti) after the French revolution was that it cause a kind of economic calamity and plunge them into financial ruin. I assume similar arguments were used in defending slavery in the US?
But I've never really heard much about the actual consequences of ending slavery, or how any economic challenges were overcome.
In the US the end of slavery was succeeded by a system of sharecropping after the failure of the reconstruction. Former slaves were for the most part reduced being sharecroppers for white land lords (who were pre-war plantation owners), which is a system in which they were allowed to work on the land owned by the landlord in exchange for 1/3 to 1/2 of their produce. The system was very exploitative and achieved essentially the same economic end of slavery; which is a supply of cheap agricultural labor who do not have to be paid in cash. By 1900 in Mississippi around 85% of all blacks were sharecroppers. The system was eventually extended to some poor whites as well (something like 30% of whites in the state were sharecroppers by this time).
The system was eventually made redundant by the mechanization of agriculture in the mid-20th century and brought to an end because there was no longer the need for a supply of cheap agricultural labor in the American south.