Perfecting a system
Give yourself time. No really. Trial and errror are your best friends, along with friendly advice when it comes to getting everything where and how you want it.
But things get a bit more interesting when you are your own R&D department. This will require knowledge of many suppliers and what they all have to offer.
Normal big box home improvement stores will carry 90% of what you will need but that other 10% is made up of electronics suppliers, container manufacturers and industrial supply houses.
304 and 316 Stainless steel fittings can be had at Grainger, usually the next day if they don’t have it in stock. Then there is McMaster-Carr but they have so much stuff sometimes it is hard to easily locate what you need, but if you look hard enough they will have it and you will probably get it the next week. Remember copper only works while the beer is still wort, once the pH changes after fermentation you do not want it to touch copper.
Amazon comes in handy sometimes for thermocouplers, PIDs and various parts thanks to thousands of 3rd party sellers.
Local shops you will come to love are usually the small hardware shops, unlike Lowes and Home Depot they have knowledgable staff and sometimes an old codger that knows exactly of something that will work for your project.
Electrical is mostly sorted out. Just have to finish designing our racking transfer system and then bottling.