Good evening OP,
I've seen a lot of great suggestions up top, and I figured I'd weigh in as well.
First off, looking for used Remington 870's, and Mossberg 500's really isn't as easy as it used to be. A lot of posts about that have me wondering whether some people have been to their local gun shops lately. If you can find one at a reasonable price, go for it, both models are solid, and have great parts/aftermarket support.
Now that we have that out of the way, let's talk Turkish imports. I like to try to shoot and review cheap guns from time to time and see how they can stand up to... Rigorous use. I actually haven't reviewed a single Turkish pump, and here's why; The issues I see with the Turkish import shotguns (not all Turkish imports but mainly just the cheap shotguns) are pretty big downsides. Turkish shotguns suffer from spotty reliability, lack of parts support, and decently long warranty wait times. A lot of the pumps are just 870 clones that have been made as cheaply as possible with little concern of end user reliability. I would rather spend a little more, and have my HD shotgun handy instead of being worried while a lemon was out for warranty work.
Now what I do recommend would be as previously stated, a Maverick 88. I have extensive experience with both maverick 88's (having owned and operated 12 of them so far) and Mossberg 500's(only have a couple of these). They work very well, have solid aftermarket support (Mossberg parts work other than forends and trigger groups), and have a US based company for support if it was ever needed. I would say for the price, you're getting a solid shotgun for just a little more.
YMMV but for HD, I wouldn't settle for the cheapest thing, but something cost effective that actually works.
P.S. I know I have a problem, but Maverick 88's are just so fun to build with and shoot.
~Leo