Moisture, subfloor conditions etc can also cause gapping.

Did you complete any moisture tests to confirm there's no mold growth?

It grows in one location because there's excess moisture allowing the mold to take proliferate.The first step is to figure out the source of moisture.

Overflowing gutters, a leaking roof, or holes in the siding may lead to moisture entering the mobile home and problems/mold in the wall cavities.Worried you’ll miss something?

HVAC duct work insulation is also deteriorated.No vapor barriers installed eitherSome fungi/mold growth notedPlumbingMultiple small leaks under sinks and from bathtub and toilets.House has Polybutylene plastic plumbing which is dangerousMain shut off valve is damagedElecticalSome small exposed wiring and bad splicing.Whole house has no GFCI's or grounding outletsInteriorMoisture spots on ceilingExteriorLose Vinyl SidingDoor Jams and Window trim have moisture damageDriveway need replacementRoofingMinor leaks noted in atticRecommended to replace roof covering, but not whole roofSome fungi growth noted in roofSo some of the question I am trying to tackle with this work is:How much should I budget for the main issues listed? 

If the tenant identifies an area of moisture that may be causing growth we immediately address the source of the moisture, replace and damage building material (usually dry wall) and or use mold cleaning solutions/mold blocking primers as required. good luck

I would not reccomend them at all in you are in an area of with alot of moisture or rain.

Also they remove the need for a chimney and individual water heaters since the exhaust is essentially moisture. our HVAC does most of their work in the city if you want contact info- He's installed 3 for us just this last year lol In basic terms It would involve:-Permits / approval-Additional Meters X 3 (all thru UGI, they coordinate with contractor)-3 additional units to accommodate each apartment.

After removing the mold risk and opening the walls we found moisture coming through the foundation showing improper foundation work done over time, including wood foundation being used in the rear.

After looking at it, it’s not really leaking or dripping, more so just a little moisture around the seal.