Light years ago there used to be a free airplane cost calculator online that had hundreds of airplane types. All you had to do was fill in the blanks and it would spit out a number.
Alas....I can’t find it anywhere.
Top of my head:
Hangarage
Insurance
Engine fund
Refurbish fund ( paint & interior & avionics)
Fuel & oil
If you’re looking for the airplane to pay for itself don’t skimp on the engine or refurbish fund.
Rental and training is a hard life and if you wish to sell in 5 years and not take a hit it needs refurbish.