The basics of a seller financed deal are that the title co or closing attorney (if there is one) or seller’s attorney draws up the warranty deed transfers title, the promissory note evidencing the debt related to the transaction, and either the deed of trust or mortgage (whichever is being used) perfecting the lien against the subject property.  

There are plenty of investments that will make you money and have mortgage paydown.

If you rent out the entire unit, you might not be able to cover more than 70% of your total monthly payments (mortgage + HOA + property taxes).

Use tools like the BiggerPockets House Hacking Calculator to analyze deals, get pre-approved for a mortgage, and begin with a manageable property to build your experience.Good luck!

There are minor functional advantages - such as cheaper closing costs due to not having to perform bank required steps.  

If you only plan on owning 2-4 properties, then there's really no harm in self-funding them unless you know a better, safer way to make more than the going interest rate on that money (most investment mortgages right now are about 7%, maybe effectively 5.5-6% after taxes depending on your brackets and tax structure).

If you plan on buying these properties using a mortgage its also best to begin the pre approval process and work with an investor friendly lender to help guide and educate you what the best product might be for your projects to make sure you dont already max out your borrowing power after the first deal.

Mortgage payment of $870 PITI with 20% down at a 7.25% investor rate.

Would the income earned by the LLC potentially qualify as eligible income for mortgage purposes in this case?

Also you would not reduce the price because of the interest payment. that is not how it works.3. yes the note could be sold, but at what type of discount and what if the borrower stopped paying.while there are a lot of posts on seller financing, some estimiate less than 1% of all transaction have seller financing and the ones that do are first position only with an average of 30% down payment - most of these are to people who do not have verifiable income.Thinking you will get conventional financing then seller financing will be uphill battle as the conventional lender most likely will not approve a 2nd mortgage for purchase.not trying to dissuade you, just wanted to provide some key insights so you do not spend 1000 hours chasing something that is impossible to find.