The guns primary purpose: To shoot tight groups at 10-15 yards and to be fun to shoot (no hassle cleaning and maintenance).
Good to see you posted here. This is a topic worthy of at least a chapter.
You did not mention CCW so will not cover that.
First you need a decent quality revolver, regardless of your primary purpose. Brand wise, to me that can only mean S&W, Ruger and Colt. Among these, the S&Ws and Rugers are easier to find and reasonably priced. Quality revolvers by nature are easy to clean and maintain.
Second, to shoot tight groups at 10 to 15 yds, most people with average skill can do this with at least a 4" barreled revolver. Skill here means the ability to see, align and hold the sights on target, plus proper trigger control.
If you wish, you can go with a 6 incher, which is even better for sight alignment. Because of the added weight upfront, recoil should be easier to manage. Some people prefer the added weight to better steady the sights on target as well. Sight recovery between shots should be quicker too. OTOH, they would be slower to swing left/right/up/down than 4 inchers, especially if they have underlugs.
Third, to be fun to shoot the gun should be of adequate weight to comfortably absorb recoil but not tire you out through a day at the range.
That would mean a medium-sized steel frame. Steel would guarantee a long useful life.
Fourth, IMO best all around caliber would be .357magnum/.38spl. Abundant, cheap (.38), powerful (.357mag), accurate, controllable, effective, versatile.
Price is a big factor though. I can't spend $400 dollars on a gun at the moment.
Is $300 bucks within range? If so, and you are willing and able to haggle, then you are in luck, because there are many good "used" S&Ws and Rugers (Double and Single Action) out there. In gun shops, police department trade-ins should fall well within that range. Try asking around, friends, neighbors, co-workers, relatives may have a piece to sell, or may know somebody who has. Look at classifieds, buy-sell papers, on-line auctions, etc. THR has a sub-forum for buying/selling as well.
Very important: If you are serious about revolvers, read the excellent sticky in this sub-forum by Jim March "Revolver Checkout Procedure". It contains valuable information that will enable you to avoid most if not all the pitfalls in buying
new or used revolvers.
Realistically within the above parameters, I'd recommend a good used .357mag/.38spl medium frame, blued or stainless 4 to 6 inch barreled S&W (model 10/13/64/65) and Rugers (Security and Service Sixes, GP100).
But I'm not worried about ammo.
Good. You reload?