I have also had success in wholesaling although I would highly recommend just becoming an agent who specializes in locating properties and negotiating them for cash buyers.
It is important to remember that a wholesaler traditionally sells their promise to purchase to another person...this means that you have entered into a contract to purchase a property. If you have no intention or chance of ever purchasing that property than you are entering into that contract in bad faith.
The solution to this is to have hard money lenders willing to lend you the money or partner up with you so that you can buy it if you cannot sell the promise to purchase.
This means that you need to:
1. Know how to evaluate the After Renovation Value.
2. Estimate the renovation figures accurately
3. Network to find reliably people who know real estate and are comfortable investing in high risk deals such as the ones you are going to be bringing them.
4. Make sure that the price that you are offering is a guaranteed deal if it is accepted by the seller, there can be no doubt in anybody's mind about this...otherwise you are exposing yourself to a lot of risk on a lot of different fronts.
I would also advise complete transparency with the seller.