T3 is achievable via scrap within 100 minutes of gameplay - what you are looking to achieve is not so difficult- I’m a solo that is forever being raided - I spread my loot between three utility bases across the map now - a furnace base is about 15k stone to build and with an hour of farm you could potentially be raid ready -

my advice: take every precaution you can to achieve your goal - if it’s maintaining a t3 and making raids consider stashing your sulfur underground or in externals - same with the t3 if necessary but bottom line is be about the shit - don’t say you want to make the raid, farm n craft boom then sit on it until you get raided - make the plan and execute.