Legal Question in Real Estate Law in Georgia

Since in Georgia you can be fired for any reason, or no reason, complaining is a good road to unemployment. Since it is their van, unless they disturbed the peace, I doubt you'd have a legal remedy unless you could prove you previously had given them notice to stay off the property.

Give them notice to not come on the property, and if they do they will be subject to arrest. When you give them the notice, give them the keys to the van because you won't need it after that.