I'm looking to extend my deer season this year, and purchase a used muzzleloader.

I have no idea what to even look for on this.

I'm looking for something affordable and we have to use iron sights here in MN.

Can I get some pointers on brands and models to look for? And also brands and models to stay away from?

Again, looking for something entry level. Used/new doesn't matter to me.  

Sent you an IM.

old school-
T/C Hawken or Renegade cannot be beat. the Renegade is my favorite Caplock. I did switch over to a musket cap.

new school-
there are several but you cannot beat a Knight Disc Extreme.

ETA I just saw RRA15 post below.

the Huntsman is a good rifle. buy a lot of the primer holders. I would buy one if I came across one, just to add to my collection.

OKNativeson
No, I have one I am thinking about selling because I don't need it.  I have an aftermarket carrierless breech plug too.
Trying to figure out on what I should price it.

Barrels alone now are selling for $225 and up.  IM me if you're interested.
Thanks RRA15

I'd recommend getting a new gun if possible.  If not, check the barrel and rifling for rust.  Also make sure the nipple and breech plug are able to be removed for cleaning.  The biggest problem with used muzzle loaders is rust.  If your state allows, an in-line gun using a 209 shotgun primer in a removable breech plug is the easiest to clean and maintain.  They have the right barrel twist for modern sabot bullets too.  Hawkins replicas and the like are great guns.  They just take a bit more effort to maintain and shoot well.  They are, however, beautiful.  You have lots to read up on.  Getting the gun and necessary tools and then finding the right bullet/powder combo is great fun.  Good luck.

For a good deal I would look at finding a CVA Wolf.  New you can get one with a cheap scope combo for under $250.  Used you can get one for around $150

1- Its nice because its a modern inline. Can take it up to 150-200 yards with the right loads.

2 It uses the 209 caps (hotter and generally more reliable)

3- It is a break open style so you can remove the breech plug making cleaning sooooo much easier.   Break open styles also have the advantage that if you accidental run your bullet in before the charge, you can get it out a lot easier than a traditional muzzle loader.  Not that I have ever done that.....  

4- Its got a good reputation for accuracy

5- You can mount a scope

6- Did I mention its cheap :)