@David RutledgeRealtor here who works with investors in both the STR and LTR markets.Consider my local area of Long Beach, CA.Most of LA and Orange County are STR-unfriendly but Long Beach just opened it’s regulations to allow non-owner occupied STRs.Aside from being a beach town in it’s own right, it is quickly becoming an aerospace hub.

If you ever get a property under contract that's occupied the best thing is to send them a letter and offer them $ for moving expenses, and get them on the phone to build some rapport. 

I have a 3 flat in Lincoln Park, Chicago, IL that I am planning to list for sale in the next 3-6 months.Currently owner occupied in 1 unit (Duplex up, 3 bed 3 bath).The other 2 units (2 bed 1 bath each) are rented.I am wondering if it is more attractive to buyers to leave the 3 bed 3 bath unit vacant when I move out, or should I place a tenant in there and then list for sale?

check with your insurance agent.. also federal law dictates that when your owner occupying your 1 to 4 unit you don't have to follow the normal fair housing laws.. you can pick and choose who you want to live in the units .. now some cities or states may have overriding rules regarding this.. but federal law is clear.. on owner occ 1 to 4.. your exempt from fair housing.so you can have a dog and you could restrict dogs for others.there is a well known list of aggressive breeds that insurance companies wont insure.. this is easy information to get.

In this type of scenario, is it still worth buying the duplex with one unit owner occupied?

Can take your time on the rehab, do some of it yourself, build your contractor network, get familiar with rehab work and costs, not have to live with roommates (house hack), get owner occupied financing, and get tax free gain on sale at the end of it. 

I went to see a tenant occupied house once and the tenant wouldn't answer the door despite having a confirmed appointment.

We are also owner-occupying our buildings so we need to know how to safe guard ourselves with boundaries as we are living in our buildings, Jesse had some similar experiences.

Most require skin in the game on deals and work like this:Rates: 10% to 14% (Most Deals are 12%)Terms: 1 Day - 24 Months (Most Deals are 6 months)Fees: 2-5 points(%) of loan amount paid at closing (Most Deals are 3 points(%))Minimum Loan Amount: $50,000 Max Loan: 65-70% of After Repair Value(ARV) 100% Rehab Financing Available (Most Deals require 20% of purchase price down payment or cross-collateral)Closing Timeframe: 48 Hours - 3 Weeks (Most Deals are 10 business days)NO PRIMARY RESIDENCES, NON-OWNER OCCUPIED ONLY, BUSINESS AND COMMERCIAL USE ONLY.

The prior prop mgr told me the owner lives in Japan.