Common fees will include a set-up fee, leasing fee for each turnover or a lease renewal fee, marking up maintenance, retaining late fees, and more.

I like the "retain ownership/continue to grow" ability the HELOC investment would provide.

The two guys I know locally that do a lot of flips (or fund flips) both started retaining select properties because of the cash flow and appreciation. 

@Joseph Berhane I would suggest retaining a lawyer with experience in Real Estate contracts.  

If you do help with a transaction you retain 100% of the commission. 

There are a number of other duplexes and triplexes on the "quality" level of mine - makes it much easier to retain the A+ tenants and avoid vacancies.

Common fees will include a set-up fee, leasing fee for each turnover or a lease renewal fee, marking up maintenance, retaining late fees, and more.

Still, there are disadvantages that may prevent a buyer or seller from signing on for owner financing.Advantages for BuyersCan provide access to financing that a borrower may not otherwise have qualified forEnables buyers to finance homes that don’t qualify for conventional financingLets buyers and sellers shorten the due diligence period for quicker closingReduces the cost of closing by eliminating appraisal costs, bank fees and—if the buyer so chooses—inspection costsEliminates down payment minimums imposed for government-backed mortgagesAdvantages for SellersAllows owners to sell their property as-is, without having to meet a lender’s appraisal requirementsPresents an investment opportunity with better returns than most traditional investmentsShortens the selling process by reducing due diligence requirements and eliminating the lending processStill offers the ability to sell the promissory note to an investor for an up-front paymentLets sellers retain title to their home—as well as money paid toward the mortgage—if the buyer defaultsDisadvantages for BuyersOften involves higher interest rates than a traditional mortgageMay require borrowers to make a balloon payment at the end of the loan termDepending on the borrower’s creditworthiness, the seller may not be willing to provide owner financingSeller’s mortgage may include a due-on-sale clause that requires them to pay off the mortgage upon selling the house, thus precluding them from offering owner financingDisadvantages for SellersExposes sellers to the risk of non-payment, subsequent default and—in some cases—a need to initiate the foreclosure processPuts seller on the hook for repairs and other consequences of deferred maintenance if the borrower defaultsFederal law may preclude sellers from offering owner financing, limit balloon payments and require the parties to involve a mortgage loan originator.All the best!

Even when you find one, the turnkey operator typically sucks out a huge amount of the profit that I can retain myself, if I simply invest in residential real estate locally.  

Does one pay a retainer and then get billed in tenths of an hour each time the client would call or email for advice?