So my answer is going to match, at least in part, some of the comments above. But I’ll spell out what I personally would recommend in total
First off - Go with Star San. forget bleach and all that. Star san.
Go to Lowes, Home Depot - any place like that. But one of their $5.00 or so buckets and a lid. Also get a spray bottle. I personally say splurge a bit and get the nicer $3 or so one versus those cheap $0.99 ones you see at the dollar store
Mix up about 2 1/2 gallons. you don’t need the full 5 gallons I think it says on the star san bottle. just cut the amount in 1/2. Use distilled water.
then, store it in your shiny new bucket. fill the spray bottle up with some too. I love having a good spray bottle with it, I run around like john wayne spraying everything in site on brew day - ha ha.
then yep - you can use it again, and again, and again. buy ph strips, use until it below 3 as noted above. having said that, I do tend to start over after maybe 3-4 batches (both fermenting and bottling). I figure 8 or so uses (4 for brewing, 4 or so for bottling) is pretty good. I may be able to get even more out of it, but the star san will last you quite awhile anyway
hope this helps