Learn the process, live through the life cycle a few times, survive some ups and downs, fail in some problems so you know what to do next time, suffer through not so good loan terms, and in the end make some money. 

Walmart is building a meat distribution center and Panasonic just broke ground on an electric vehicle battery plant.

In my city the treatment plant water keeps failing Epa health contaminant limits.

Google actually has a data plant there.

The most reasonable approach here, since your friends are suffering from what they think is mold issues, is for them to move somewhere else that doesn't have any mold. 

It can be rented to a church for a yard sale, a farmer for planting a garden, a parking lot for when people next door hold a party or other function.  

Home to The Ohio State University with nearly 60,000 students, 5 fortune 500 companies, over +25% population change since 2000, 2016 smart city challenge award winner gaining 50 million dollars in funding from the government, Intel is spending 20 Billion dollars to build two semiconductor plants, and many many more great things presently and coming in the future.

Originally posted by @Michael Plante:Could easily come out much higher if they ‘find’ more problems when they dig things out I would ask seller to pay And if they won’t, unless it is a KILLER deal I would move on Thanks @Michael Plante  So true...they always seem to find other things with these older homes when you start digging.....

The experience in these towns will suffer enormously if there is no one to wait tables, bump chairs at the resort, plow the roads or clean the rental rooms etc.The Town of Breckenridge just bought a number of condos at around market value, put deed restrictions on them and listed them for $160-180k less than they paid to give a few more options to locals that work 30+ hours a week in the county.

If you plan on trying to run a storage facility through 100% automation your facility will suffer a bit.