isn't the probe too sensitive?
Kind of. It's sensitive to ion differentials. So if you store in deionized or distilled water, it will pull KCl (most probes) or whatever the solution is through. Otherwise, nah.
Seems to me it takes care of steps 1 & 2 easily. Pretty cheap too!
Yep, but remember this is for stubborn protein deposits. You can also use a bleach solution and a 10 min soak. oh and no, te renu liquid is not foil oil removal. that takes a degreaser.
Is there a household product I can use for this? and how would I use it? (dilution rate, etc)
Yes, salt replacer is KCl. But it's super cheap to buy online if you can't find. like $4/lb cheap. Make saturated solution. Not sure what more you need. Saturated solution is made when no more salt dissolves. Heat the water up so it's faster. Or if you want calculate the molarity.
Or just buy commercial probe cleaner for $10 and soak in that for half a day. It usually does the job, although not quite as thorough as a full reconditioning process.
Also check the probe temp tolerances for the KCl soak. some should not go beyond 50-60C.