u/IndependentPickle230

Hi everyone, I’m looking at getting a bakfiets cargo bike to ferry my two children (4 and 7) to school (25 min ride each way on my non-electric, non-cargo bike) and around our town. It’s flat but windy here. Given the age of my children, and based on advice on this sub, I think I probably need an e-cargo bike, but unfortunately even second hand they are out of my budget. Secondhand urban arrows are listed for £3500 on fb. I have seen non-electric bakfiets style bikes (Dolly) that I can afford. If I bought a non-electric cargo bike, would it be easy enough (for a bike shop!) and safe enough to convert to electric? The non-electric bikes I’ve seen have roller brakes I think, not the hydraulic disc brakes of the bikes designed to be electric. Is this an issue? Can it be overcome? Is there anything else I need to consider in a conversion or buying secondhand? Thanks so much in advance!