I'm starting a property management company and I'm curious to know how people have marketed themselves online.

It is not that good at the price point of DC or in my market (but better than my market).  

These cities are the well known, sub 100k markets in the US.

There are really great REI opportunities in different markets - markets in the Midwest and Southeast of the country are particularly lucrative - where not only are the purchase prices reasonable for most RE investors, but the homes are turnkey (new builds or completely rehabbed homes, tenant ready, systems 10 years of life remaining on them, property management teams in place) with appreciating home value AND appreciating rent.

Like @Chris Seveney said, private lending is a great way to go as well.  

Recently, our real estate agent did a market analysis and estimates we can sell for between $575K-$585K, resulting in a net gain after all of our fees of about $100K.

However, if your father inherits and later transfers the home, it should qualify for a step-up in basis to fair market value, reducing future tax liability.If the goal is to tap into equity, having the trust take out a HELOC may be a better option, avoiding California Prop 19 reassessment, which could raise property taxes significantly.

Quick question on those who have done seller financing:- Buying a 0.3 acre downtown fort lauderdale multi family, negotiated an around 1M price w lot of development rights, double lot. seller got it way back early 90s for pennies- got good credit 800+, w2 job etc put 40% down and mortgage bank offered 6.62% 30yr fixed (CF negative as this would make current rent roll not too much compared to the PITI)- property is in ok condition, needs 20-30k repairs which seller OKd, and all 3 tenants are month to month, pay bit under market but also ok- seller would like to do seller financing, interest only at 5.75%, 30yr amortization at 7yr balloon (CF would be positive) - id be paying some principal as well, just to grow some equity- buying this deal for the future development of the area (las olas, kushner broward crossing) so not really worried even if we overpay for it now, but never done creative finance as i always relied on a strong W2 job to get good loans but obv im used to 3% 30yr rates from covid times not this 6+ environment..Goal is to hold the property 3-5yrs, and then actually develop it or sell half the land / refinance, pull out HELOC if it appreciates.Questions:1) What does he know that i dont? 

I think it's very dependent on the property and market. 

Instead of following trends, tailor your space to the lifestyle of your target market.