You will at least need new wheel seals, which are Dexter #010-036-00 or just #10-36. I tried to not use other brands of backing plate/brake assemblies. The Dexter assemblies are USA made and usually hold up quite well. If everything is good, maybe a pound of high quality grease, the four seals, rags and solvent to clean the bearings are all you should need. If you need new brake assemblies, you should be able to get them for a bit more than $100 per wheel. The assemblies come either RH or LH for the right or left side of the axle. I've used Redneck Trailer supply in the past. https://shop.redneck-trailer.com/p-3...ke-23-465.aspx
You don't say what year your rig is, but if it is new enough, you might be lucky to have the hydraulic leveling system which will make servicing your brakes and bearings much easier.