Wholesaling conceptually is easy, but I dont know anyone who is doing that and making good living from it, I do know plenty of sucessfull rehabbers.
Sounds like you have already sucessfully rehabbed and rented and rehabbed and flipped a few. I would think vwith your experience I it would be much easier to gear up your rehab game to make good money then learning how to become a sucessfull wholesaler.
Couple options to find the money. If you put a portfolio together of the houses you have done and show the profits you have made, you can likely find a private lender, or partner.
Couple options, and a lot of variables within these to cut and paste to fit your needs circumstances
1. You can partner with a money partner, you do the work split the profits, I did many of those in the early days, 50/50 to start with, then 60/40 then .....
I would agree to give them a minimum 10% return before I would get paid if profit split didnt provide at least that for them, gave them a bit of extra confidence.
2. Private lender; there are a lot of people getting 1-5% returns on their investment. If you offer them 5%-10% odds are with a bit of effort you can find a lender, i have used 15-20 different private lenders in thepast 10 years, currently using two main ones and three who do one or two at a time. If you and your husband sit down and do the 20 Question method, odds are you will find a couple lenders within a week. Take pad and paper and write down how much you need for your next deal, then write down, in about 10-15 minutes, 20 people you know, that would have enough money to do such a deal, if they wanted to. Dont worry about if they would want to at this point. Can be friends, relatives, business acquaintances, enemies :-), church acquaintances, realtors, attorneys, old friends, new friends... when you have them written down, take the top three you think would be most likely to do a deal, or that you would be most comfortable asking, is not a bad place to start to practice, meet them for coffee, run the concept past them, odds are by the time you have run this past 3-5 you will have a lender/partner or two. The first one or two are the most scary, after that it becomes fun. The people that do one, tend to do another, then two at a time, then the brag to their friends how much money they are making then their friends want to loan to you, and you can start reducing interest rates.
3. Borrow money from a small local lender, if you have some money to work with, there are plenty off banks, even conservetive ones tend to lend 80%: of purchase price, and you use your money for the 20% and the rehab. Some will loan 80% and give you all the rehab money. On rare occassion, we have one of those, we close with cash, they do an immediate refinance and give us all the rehab money, to a max of 80% of arv, those take some history and relationship building, but doable.
4. Finance the purchase at 80% with lender,
borrow the rest with a heloc or loc against another property.
Some ideas for you, hope that helps and good luck with your rehab adventures.