Hopefully the majority of the partners and pax are under 150lbs!
Not trying to be facetious but for $28K I'd throw in an extra 15k (peanuts on a 20 year note) and get the extra useful load of a C172. Otherwise, you're at 2 hrs fuel or less with 2 persons, especially in the 150 at 10 lower HP. I've owned a 1976 M model C172 and an 81 P model, both of which I obtained for under 40K. Plus you've got the ability to do IFR work in the 172.
I was going to buy my wife (a former FA now learning to fly) a C152 but we've got no utility here in Dallas at 103 degrees.
I've also been in the aircraft sales business and most banks will not finance an aircraft less than 25K, so you're going to have to cash it out if you go that route.