Any advice for new rabbit owner?

I am getting two female bunnies for an easter pressie to myself and my brother they are Dwarf Lop and an Mini Lop i believe a sooty fawn Colour and an bluey black Colour when i get them they will be 8 weeks old what i am wondering is i already have their hutch set up and just need to get a water drippier bottle for them to drink from as they are from separate litters i'm hoping they will get along i have done a bit of research on them but alot of the research i have found is all american units :/ i was wondering how big they will grow to in KG ? and if anyone has any good advice on being a rabbit owner they have been raised around dogs and i have 3 little dogs which will be fine around them :) i just want some info from people who have owned rabbits THANKS GUYS !!