Also study costs of roof replacements, furnaces and water heaters.

The water is always cold, but at least in the summer it is nice outside of the water and the winter air temps are probably higher than the Tahoe winter air temps. 

Without knowing more about the location though, if this cabin has direct water views and is able to sleep at least 6 people, a fully renovated version of your cabin could probably pull in at least $600/night in the summer without much effort. 

Plus its a non stop location for tourism Summer Camping, White Water Rafting, Rock climbing, 4 Wheeler/ATV, Hunting, Fishing.Winter - Ski, Snowboard, Tube, Ice Fishing, Hunting, Winter Breaks away from the Heat etc.

The reason I ask if it used to ascertain damage to something on the lot (water/sewer/utilities hookups or something) and you don't have pics and mutually signed documentation from the lessor/lessee upon each tenant's move in prior to your ownership, would you be able to justify a charge upon move out?

He proposed 2% which would be $8,000, does this seem fair or standard?

Depending on Loss History, how long the lapses was, use of buildings, age of building and updates, etc. there may be a Standard Market. 

Of course, the wear and tear was through the roof and the water heater or HVAC never seemed to perform to his liking when it is summer and you have 14 breathing, walking talking 98.6F meat-sicles in the house warming it up.  

Industry standard is 10-25%

Thank you for taking time to share your thoughts.The roof has been largely replaced and a new heating system and water tank was put in a few years ago.