Wholesale
You find the property, negotiate with the current owner to buy the property, then sell that contract to another investor who will do the rehab, put tenants in there, or sell.
Rehaber, or flipper
You either find the property or buy from a wholesaler. Rehab and make profit on the sale
Everyone has strengths and weaknesses. If you are not good at marketing and negotiations, maybe finding the properties is not for you. If you are not handy or don't know the trades, find a general contractor. Don't want to deal with tenants, there are property managers out there that can just find you qualified tenants or take over the running of the rental, including the late night toilet calls.
You don't have to do it all. Outsource what you don't like or don't know. I know people who buy from wholesalers, have a GC do the rehab, then turn it over to a manager. Granted, they are not making as much money as they would if they did more DIY, but they are still making money.