Tim:
Without knowing where you live or will keep the airplane, it's difficult to provide an estimate. My sense, however, is that $4k annual fixed cost is high, unless you are adding in repayment of principal. Using principal for an airplane is a cost, but I think most exclude it when computing annual owning and operating costs.
When I was trying to buy a 150, I calculated that it would cost me $2,100 to 2,400 every year (I'm in Oklahoma), depending upon where I hanagared it, just to have the airplane and keep it in annual. That figure included hangar rent; insurance -- $1 million liability and in-motion hull coverage (I don't remember the deductable); and cost of annual with no major repairs. It did not include, depreciation, lost interest on the money invested in the airplane, or operating maintenance costs and engine reserve.
My fixed costs absorbed more than one-half of the discretionary money I had for flying and that's a lot. Local rental rates generally would have let me fly about 10 more hours a year for the same amount of money as I would have been paying as an owner. As an owner, I figured that for the money I had available, I could fly about 50 hours per year at an hourly cost of $91.00.
So, I had to decide what was my flying goal? Full ownership and all of the convenience, accessiblity, and financial responsiblities that go with it, or fractional ownership and reduced financial committment and obligations with a corresponding reduction in accessiblity and convenience?
I chose the later and a partnership arrangement which has worked extremely well for me. For about 1/3 of the capital outlay I would have spent for full ownership, I can fly about 70 hours per year for the same amount of money, in an airplane hangared only 10 minutes from my house, virtually whenever I want to with the knowledge that three others will be sharing the costs of hangar, insurance, and any maintenance issues that arise. In the seven months I have been a partner I have not encountered a single conflicting access issue.
Most people on this forum, with a couple of exceptions have chosen full ownership and the financial obligations that go with it. It's a choice that we must make at some point, and it sounds like you are at that point now.
Full ownership is a little easier choice if the potential owner is also an A&P or has good mechanical skills and a place to work on an airplane. Unfortunately for me, I have none of those talents or resources.
In any case, airplane ownership, full or fractional, is somewhat of a gamble, but it is usually so desirable, we are willing to take some big chances on the venture. You are the only one who knows your resources and what you want. You are the only one who can make the choice. Good luck and best wishes to you for success in whatever avenue you follow.
Don
