They charge an acquisition, disposition and management fees.

I've been in a few that required professional carpet cleaning upon move out - either show proof of the cleaning with receipt or they would charge you the fee for them to hire it out.

Asked for $675 fee. 

or the whole amount of debt they owe originally before the plan?

The fact you are asking, is there is a loan for this only proves my point, Show it to someone doing deals, IF its good they will pay you a finder's fee.

Several methods come to mind for the ADU.   1) a regular or periodically adjusted flat fee (based on an estimated usage); 2) factored into the rent (essentially the same as a flat fee); 3) percentage proportionally based on sqft. 

Price point for Hostfully is approximately $1200 per year and they do charge an onboarding fee that includes a pair of individual train g sessions done online.  

Their insights highlight the necessity for a careful approach to vapor barriers and insulation, emphasizing compatibility with the building's original design and moisture management needs.Here's the plan:Ceilings/Attic Floors: Elevate insulation to R-38 or above, incorporating vapor retarder paint or smart vapor retarders for optimal moisture management.Walls: Boost insulation to R-13 or more, utilizing smart vapor retarders or materials with adjustable permeability.Basements, Crawl Spaces: Increase insulation to R-19, targeting ground moisture and internal humidity control.Materials: Opt for eco-friendly, breathable insulation and vapor barrier materials that preserve the building's historic charm.This meticulous approach elevates the property's energy efficiency and moisture management, enhancing its value and ensuring a profitable return without compromising its architectural integrity.I'd like to hear your thoughts, experiences, or any advice you might have on integrating vapor barriers and insulation in renovating historic properties.

The comps are between $118-$141/sqft, but it was purchased at $148/sqft.The loan is assumable at 2.75% rate ($139,383 principal remaining) but will cost $900 application fee and  between 1-5% of purchase price (assuming 2.5%).

Originally posted by @Bruce Woodruff:It is not that easy to produce a great looking paint job.