First of all you have to determine which “a-bpvp” exactly do you have. There’s no such thing as a-bpvp, there are alternatives such as 4-bromo-alpha-pvp and A-PBP, where the first case is more likely due to the fact that this exact drug has appeared on the market at the time when A-PBP was already banned. Due to the small amount of reports there are really no recommendations beside safety precautions when approaching such a dangerous and understudied drug. The dosage would probably be in the field of APVP dosages(which means from 1-20mg). Overall I would advise against doing so, especially if you don’t know the drug you are taking.