But, over time can tell people that give concrete metrics & specific examples vs. sharing feelings & imos :) 

Does anyone have more concrete detailed information on this?

But they do end up with a concrete number to justify any increased costs. 

Paying down on a rental is a cash-flow, equity decision.Paying off the home is a security, equity decision.If your feet are in concrete like mine, cast out the anchor and moor yourself to the community.

Also, for the analysis and foundation, they will likely recommend companies to do soil studies, engineering testing such as concrete, etc...

There are vendors in many locations whose business includes pouring concrete floors in crawl spaces to eliminate the issues you describe.

I've heard of guys using a concrete sealer prior to installation, but I wouldn't recommend that because it could mess with the mortar adhering to the subfloor properly.  

I'm still watching it, him, and his other property for some solid evidence.If I don't see anything concrete before the 60 day move in requirement I am going to hire a private investigator to gather evidence.

Had about 54 cats that animal rescue pulled out of it.They got into the crawl space vent guard that was broken.The owner was a woman who loved pets but had mental health issues.Luckily the house only had a tiny mortgage on it relative to it's value.Cat urine was everywhere.We were able to eliminate it everywhere accept one room where she closed the door and 25 cats were in there.To get rid of that smell you had to tear the sheetrock down and replace the subfloors and Kilz everything.I sold it and collected my check to a cash investor.The lady kept 3 cats that were deemed healthy and moved into a big apartment complex facility that was a loft style with concrete floors.It was an old factory conversion into a 300 unit apartment complex.Had another property I did a Interior BPO on in pre-list for an REO.Owners had left dogs inside living there for 4 weeks with food to survive on.There were literally thousands of terds on every level of the 3 story house along with urine and clothes left behind.This was a few years old house in an upscale neighborhood of 500,000 to 600,000 homes.The neighbors came by and couldn't believe what they were seeing.So I will again say it's not about the pets but the owners who take care of them.On credit in my area most tenants have bad credit.If they have great credit they are buying a house for dirt cheap.The only reason they wouldn't is if they are staying for a short time or in transition.Why pay some landlord who could get foreclosed on 800 a month in rent for a 3 bed 2 bath when you can buy one for cheap.In my area you could get a mortgage and pay 500 a month for that same house.Many times people with good credit are ticking time bombs.They actually are not a great candidate but have just kept acquiring more debt to pay what they have until reaching critical mass.These types carrying a bunch of debt have bankruptcy in there future.When you rent to tenant out of a chapter 7 many have a fresh start and have income to pay the rent.So every renter is a case by case basis even though there are common traits involved.

It has a concrete tile roof and is finished with stucco , so the first significant maintenance item will probably be a water heater.