Yes but you if you want to ensure your plant will stay healthy the entire run use a clean water source and add in some worm castings and a slow release fertilizer before you start vegging them.
It is better to transplant once or twice than to try and go the full grow in a 5gal. Use Jobes organic spikes for bloom phase; they feed for 8 week. I never mainline so I have no idea. Using fabric containers virtually eliminates root bind.
You can use any decent organic soil as it is to start your plants but if you want to avoid needing to add anything later on in the grow add fertilizer and compost.
I will probably build my own after a while based off the Coots mix, but a little different. I'm just not in the spot now to drop the extra money, atm. I'd rather not use ffof b/c of it's short life but that is what I have along with some Rootwise mycrobe, Build a soil craft blend as well as BAS top dress and some EWC.
You can; soil doesn't deplete. It just becomes inactive microbially. I've been using the same ffof soil (among other brands) for years just re-amend with ewc and ferts.
Go check out my thread in the organic section called dick dies dank. There's a book listed you should read true living organics by the Rev. Has everything you need to go water only. Compost is the key
BAS is a waste of your money. You can build your own mix much cheaper than BAS but amending an existing mix like ffof or what have you is def more cost effective. You don't need everything at once just start with what you have and squire stuff as you go
That's aquire not squire wtf autocorrect...start up a worm bin and you'll have free ewc to charge up your soil for life. I basically feed my plants otchen scraps. Cost = zero