Going forward, put a generalized clause in your lease that prevents a tenant from disturbing the "quiet enjoyment" of the cohabitants of the building.

If they're disturbed, doped up, illiterate, the psychology/logic of most deterrents will be lost having no effect.

Asbestos was used in many materials throughout buildings - stucco; window putty; asbestos-cement shingles, pipes, and flues; pipe, duct, and vessel insulation; sheet vinyl flooring; drywall joint compound (so over much of the drywall surface); plaster; floor tile (all sizes); flooring, mirror, ceiling tile, and other mastics; roofing; plastic roof cement; roof coatings; acoustic ceiling texture; ceiling tile; and more.Lead-based paint coated with non-lead-based paint in good condition is less of an issue, as long as it is maintained, and is not damaged or disturbed, as by repair and renovation work, or deterioration.

Im doing smaller urban plots with my orchard so I have to be conscientious of neighbors so I am not disturbing them with a large population of bees.

If you disturb so much of a lead based paint area you have to use someone that is certified.

As for the "disturbing" reality of the missing criminal information on the report I can tell you that you will run into this problem everywhere.

Ironic that your website states "Please do not disturb the tenants"  AND "showings by appointment only"  LOL!

As I said, I can adjust the rents on the tenants to cover my extra costs without disturbing the relationship very much.

If it's easier to open up the back side common wall with out disturbing the shower surround do that before ceiling,under the leak, the water is coming from above and ceiling opening is just probably not going to  give you a clear point of where to start repair all the fittings and valves are up to high 

On my properties, I generally choose to not disturb it.