It really depends on your requirements. A VFR-only Cessna 152 or Piper Warrior is economical. However, if your requirements are six seats, IFR, and known icing the cost goes up significantly.
I found a few nice Saratogas with GTN750, ADS-B IN/OUT compliant, and operable autopilots available for around $300k. Getting a known-icing system installed would have added just under $50k to the cost of the airplane. The down payment would have been about $60k (if I could find a seller and bank willing to roll the cost of known icing into the purchase.)
There are also the day-one costs for the airplane. Avionics needs subscriptions, with a single engine you want a solid battery, how is the fly-away kit it probably needs replenishment. Then the costs of inspection and going to get the airplane. You can expect to budget another 3% or almost $10K.
I can’t land a Saratoga in my backyard. So that means the monthly cost of renting a hangar—is about $300 per month. Then there is insurance. A big single like a PA-32 will cost some money even for a 10,000-hour CFI/CFII with PA-32-301 time in my logbooks. Budget another $200 per month for insurance.
So monthly costs would work out to about $2,500 for the loan, $300 for the hangar, $200 for insurance, first-year avionics subscriptions and Foreflight paid upfront. So $3,000 per month without logging one flight hour on the airplane.
Taking the airplane out will cost about $320 per hour (with the engine, inspections, and maintenance reserve built in.) Yep, a Saratoga is low-end twin money to fly. So if I fly the PA-32 10 hours per month then I am looking at another $3,200.
So about $6,200 per month to own and fly a real six-seat, known icing, IFR capable airplane. This does not even include the costs of going someplace such as ramp fees, landing fees, rental cars, and hotels.
A cost of about $145,000 for the first year and $77,000 per subsequent year (adding avionics subscriptions) to own and fly an airplane that I felt comfortably safe carrying my family was too rich for my blood. So I bought a motorhome instead.