Try using one of those sponges you buy in the tile dept that has an abrasive side.

Mourning takes time so to not be abrasive is to be smart, but it's a fine line that has to be walked, no doubt. 

Granted, you don't want to be rude or abrasive in your undertaking -- you should be courteous but firm.

Keep in mind this is with me taking care of it with kid gloves and using gentle, non-abrasive cleaners because I'm the actual owner.

I was a little abrasive with a couple folks who keep posting properties but never follow up once they get my contact information.

@Uzi Pablo this may sound abrasive but where you shine in business ( not even knowing what business it is that you sold ) your more than likely lack in other skill sets and that as you know since your a smart guy is what you don’t know that you don’t know will kill you in business.You need to beef up your sales and negotiating skills before you even think about investing in real estate.Fundamentals are the key to big gains and wins.

Abrasive blast, shot-blast, water jet or mechanically abrade concrete surfaces to remove laitance, curing compounds, hardeners, sealers and other contaminants and to provide a minimum ICRI-CSP 5 surface profile.

Generally mitigation/abatement involves some or all of the following: drywall removal, abrasive sanding, wet wiping with biocide, HEPA air scrubbing, structural drying before repairs performed if moisture remains, etc.2) I would check with your State R/E disclosure laws.

Epoxy flooring systems have exceptional abrasion resistance.

This will loosen all soil and old finishes from the tile.4) Scrub the floor vigorously, using the abrasive edge of the mop in a back and forth motion.