Ideally, its best to sell them together but whether or not you "list" them together depends on what the other sellers are doing in your building. If the other ones separate them out but you add yours into the list price, you may look "overpriced" when listings in your building show up on searches. Unfortunately, that could be the fine line between getting a showing scheduled or not. If you do separate them, you need to understand that the buyer then is NOT obliged to buy the parking and you may be stuck selling it on your own and there are pros & cons to that as well. If parking is high in demand in your building, its great but if not, you could get into trouble. Also check to make sure that the building will allow you to close on your unit if you still own the parking space. Many do not allow it as they have strict rules that only owners of units can own spaces so they can hold up your closing until you show that you no longer own the space or are transferring it in the unit sale. I also do not agree that you will get a better price if you list them separately because it is very common for buyers to try to "add the space" into the deal for the asking price so keep that in mind when determining your list price. If parking is high in demand in your building and the buyer does want it, then you should be able to get top dollar for it, just make sure you have enough time and/or resources to find a buyer for it. You may even want to pre-market the space before your list to see if you can find potential buyers for the space and let them know that they will be on a list in the event the buyer (always offer it to the unit buyer first) doesn't want it.