Since you are just starting, you could look into WVO instead of BioD. WVO is just filtered and dewatered veggie oil, and BioD is chemically treated veggie oil. The goal of running any veggie oil in a Diesel engine is to lower the viscosity of the oil to something close to the viscosity of Diesel. So, you can either heat it from the tank to the IP (WVO) or chemically treat the veggie oil (BioD). The upfront cost is more to install a two-tank WVO system, but the cost of processing WVO is nearly nothing since it is just filtering and settling. The upfront cost of BioD is less (replacing seals and hoses), but it costs more to make your own BioD in the long run.

Up to you. There are other pros and cons.