Ultimately, per @Christopher Phillips link, the residual land value analysis is the preferred methodology.

The thrid step is cleaning the area with soap and water and then treating with a residual chemical.

.- Soil extraction with low moisture steam- Application of fabric softener and color brighteners removes detergent residue according to manufacturers specifications, leaving fibers bright and soft with a silky feel.

Next is to start a business in the US with some of their "residual" cash.

I myself have been doing real estate for 3 years and now have decided to venture into acquiring rental properties for residual income for retirement.

If you squeeze too hard on these you can get all kinds of residual issues.  

I recommend shooting cabinets with an airless paint sprayer if you want them to look good without residual fibers from a roller or orange peeling/brush streaking.

If done after the rehab, it provides an opportunity to address residual issues prior to putting the property on the market, although the downside is that it could mean tearing out newly installed flooring, cabinets, and appliances to address serious problems like mould underneath the subfloor that we’re not initially identified.Any thoughts?

I pulled up carpet and linoleum tile and now it is cement with glue residue.

I often see a 2% selling cost subtracted from a residual value in the direct cap or DCF valuation method for commercial deals.