At any rate it is possible, but depending on your appraisal it could be a gamble

Ton's of people with golden shackles of sub 3% rates, epic net shortage, skilled labor shortage, on and on. 

At CA tax rates it doesn't take much to be a significant number!  

I offered them 10% down, interest rates favorable to me, amortized for 30 years, but with a balloon payment after 3-5 years.

Coupled with persistently high interest rates that may last for years, rising insurance premiums are inevitable, regardless of your property’s condition.

My in-laws loaned us the total purchase price minus $5,000 on a 3% interest rate.

I agree with the others here that say you need to have some skin in the game, if you are going to live there yourself, get an FHA loan rather than owner financing, you can get a 3.5% down loan, personally I do not love these as they require  PMI which is an additional expense, and you also need  bring additional funds for closing at least for taxes, title, attorney and transfer fees . borrowing from anyone else for the down payment, to include a personal loan from the bank is not a good idea, those again will be higher int. rate.

my experience has been (1) I can obtain the same rental rate for a 6 month lease that I can for a 60 day “stay” if FULLY furnished (2) some of these 6 month rental turn into 2 years or more.  

Selling for $380k means an $80k taxable gain at long-term capital gains rates (0%, 15%, or 20%, depending on income).The $80k HELOC used for personal debts doesn’t affect your taxes.A 1031 exchange could defer taxes, but you’d need to reinvest in another investment property, not a home for your mom.

@Iris Olivas Most local banks/credit unions can do this deal with lower fees and potentially rates than brokers.