Determining value of detached guest house

[Christian Ramirez]

Alright Im a bit confused here on how much value this guest house can add to the property.

So the main house is a 2 bed 1 bath 856 sq ft with a detached  1 bed 1 bath guest house is the back yard measuring at 342 sq ft. This seller was renting the guest house at  $750 a month while living in the main house. 

The question is how do I determine the value of this guest house and how it affects ARV on this house when this is the only property in the area that has a detached guest house.

[Gianny Niebla]

Quote from @Christian Ramirez:

Alright Im a bit confused here on how much value this guest house can add to the property.

So the main house is a 2 bed 1 bath 856 sq ft with a detached  1 bed 1 bath guest house is the back yard measuring at 342 sq ft. This seller was renting the guest house at  $750 a month while living in the main house. 

The question is how do I determine the value of this guest house and how it affects ARV on this house when this is the only property in the area that has a detached guest house.

 I am going to assume that the structure was originally a shed. Then converted into a 1 bedroom. If this is a legal duplex then the rental income will be taken into consideration and that will help your arv a lot. In most parts of Miami a 300 sq ft apt will rent for $1200. If this is the case it has maybe 10-20k of value to an appraiser. In the event that this is a legal living unit I would say it would be worth around 75k due to the income it produces and your comps would be other duplex's.