When I was in my 20's I could barely afford pants.
In fairness I bought a Skywagon at 23, but that came with it being my only goal in life for a decade. An engineering degree, and a co-op (and internships) where I regularly worked 80 hours weeks to build up enough to buy it in cash with enough leftover for maintenance.
That being said, I'm inclined to agree that maybe aircraft ownership isn't (yet) the best idea for the OP. Sure a 150 is a lot cheaper than a 180, but there are so many things that go into aircraft purchases regardless of the plane:
Purchase costs (pre-buy)
Cost to go see the plane (flight, hotel, rental car)
Cost to ferry the plane home
Aircraft sales tax
Aircraft registration
A canopy cover
Safety wire tools
Oil
Fuel
Unexpected Mx items (they happen and you need to be ready for them)
Tiedown/Hangar
Insurance
Tires
New lightbulbs as old ones burn out
old avionics need maintenance
Nylon rope to tie the plane down
I just spent $60 on new anti-chafe tape for the cowling
I'm fairly certain I'm now Aircraft Spruce's biggest customer
.
It all adds up... and fast. These initial costs fade away as you own it for longer because many are one-time things, but you still gotta buy them. I wouldn't trade plane ownership for anything, but you have to be prepared for it financially and mentally. Even a 150 can run up a tab.
And if you're not ready for it, it can wipe you out financially and/or the plane is going to sit and rot and be worth nothing.