You'll probably out grow of a PA28 / C172 real quick.
I know that would be true of me. On the other hand, there are many, many private owners of such 'spam cans', and most are very happy with their airplanes. And they are relatively easy to sell, if an owner later wants to 'trade up'.
Generally speaking, I would advise any first-time owner to adhere to the 'KISS principle' and avoid high performance airplanes like Mooneys. Learning how to look after an airplane is difficult enough without worrying about maintenance routines for variable-pitch airscrews, retractable undercarriage, turbocharged engines, etc. If speed is very important, there are simple-but-reasonably-fast airplanes (e.g., the
Grumman Cheetah or Tiger) that would be a better choice than a Mooney.
P.S. Of course, I just wrote the above for fun, and without naïvely imagining that anyone listens to me. If Captain Noodle decides that he must have a Mooney as a first airplane, he should at least read
these articles on pre-purchase inspections.
P.P.S. Speaking of pre-purchase inspections,
this article is specifically targeted at Ercoupes, but much of its contents are of general application. Chapter 5 ("Acceptance and Pre-purchase Checks") in
Rules & Inspections (1987), ISBN 0-9615196-1-4, is also useful reading.