Buy condo or apartment for primary residence

[Sufyan Minhas]

Hello I needed some advice about my idea. I am located in new york city. I am looking to buy a condo or apartment in nyc five borough area or any neighbouring counties( Long Island, Westchester). The reason is because I will get to save on rent and will get to know how real estate market works. My question is will I be able to rent it out after I pay it off and want to move somewhere else. I have heard that some co-ops chsnge their policies often and do not allow subletting. They dont want anybody other than condo owner to occupy the property. Someone told me its very hard to sell these properties and you have to sell them at a loss if you want to get rid of them. Can anybody tell me how it works. What i have in mind is doable or not?