In NY, yes it has, can and will pose issue if your purchaser do not want tenants in the home. Most buyers I work with are first time buyers, they are looking for a home to move into to begin a family, not a home where they have to wait, and hope that a tenant will move out.
Like others have stated, it depends on your buyer... it can be an issue, or perhaps not. However I find that when tenant occupies a home that is for sale, I have had more problems with it than not. Holding up closings etc etc... more