Djb
The building and safety division of the municipality in which the home is located will have the permits on file. IN most cases the only real challenge will arise if an owner wants to have work done on the property. For example, if the owner wanted to add on a bedroom and a bath, and the inspector found unsafe areas of the house while working on that project, there may be some requirements to have the previous work brought up to code.

A smart buyer will pull the permits prior to buying. One option is to pull the permits and look them over. Unpermitted work cannot be used in the marketing of the property. For example, if the records show a two bedroom, and you now have three bedrooms, because only two bedrooms are permitted, you can only market it as a two bedroom.

The township or city offices would have records of the permits if they had been pulled. If the permits were not pulled, you might run into problems if the city wishes to inspect the property. If work was completed that was against city zoning code, you could be fined and forced to remove the addition. Each case is different, but you want to keep that in mind. It might be worth it to look up the local zoning code for the property to identify if what has been done is within the regulations. If you have any further questions please feel free to contact me.