I don't know how many properties you have, but I've only got the one and this is our first long-term tenant (previously furnished MTR).

In 2021, after completing the BiggerPockets STR course and analyzing market data, we transitioned the property to a fully furnished premium short-term rental after the tenant moved out.

Since a it's multi-unit, I'd probably only furnishing one unit and LTR the other(s) like others are saying.

I would expect start-up costs such as stocking linens/bedding, upgrading certain furnishing and amenities, and pass-through costs for listing on the OTAs (like VRBO, Airbnb). 

But I have also opened up new cards for specific properties if there is a nice sign up bonus for a card that I know I will hit during the rehab and furnishing phase.

Many resemble the pad Sinwar was in when the IDF took him out.

STR income will always be dependent on who I managing the property, how nice the finishes and furnishings are, and the actual location of a property within the given city.With my STR in Destin, numbers are more or less the same as last year, perhaps down just a hair. 

My neighbor is renting her Jr.attached ADU: 2 bedroom, 1 bathroom, 825sq -furnished- $2500/mo (utilities incl./ current tenant renting for 6mo).LOFTI have plenty of land for detached ADU /their own yard, driveway & entry with the goal of a 1 bedroom/1 full bathroom downstairs & a bedroom/powder room upstairs <so 1 & 1/4 bath>...

I tried furnishing a few times in 2019.

I am thinking near $400/month per unit including furnishings.  2 units would be $9600.