Thanks for all the responses.
I already have an 870 (12 gauge). I bought it around 1980. It's beautiful and looks brand new, with a glossy walnu stock. I've used it a few times on jacks and it was too easy. I think I need a bit more of a challenge. I thought it was a bit cumbersome though, especially with the 28" pipe.
I just purchased a CZ 720 auto-loader (20 gauge), with a walnut stock. I bought it new in the box, from Bud's for $340. It weighs only 6.3 lbs. It's the short stock version, with a 24" barrel and a 13" LOP. I have some health problems and I need something easy to carry on those all day hikes out in the desert. I plan on sticking a thicker recoil pad on it, or use spacers, to extend the LOP to about 13.5". Ideas on the best way to do this are welcome. The other CZ auto's had 14.5" LOP's. That's a wee bit long for me, if I go by the distance between my thumb and nose. I will pass it down to my son in a few years, when he is ready. Of course, an H&R Single-Shot comes first.