i use my dad snap on double flare kit for making brake or gas lines but i have used cheap ones and they will usually make a good brake line if you know what your doing.

i hate unions. i usually use 1 solid line even if the lines are a pain to make. any unions used on my trucks were installed by previous owners. i think between my 81 and 93 i have remover 3-4 unions. just make sure when running the lines to rap the fitting and end of the brake line with electrical tape or something like that while you are feeding it through the frame so that no dirt gets in it.