Given what you say, would it cost you better than $6000 a year in custom costs? ( Your local pricing ).
You already have 65 - 75 horse or better tractor?
I'd say go for it. I paid $7200 cdn for a used NH 688 haybine $12000 for a used NH 634 baler and too much for a new NH tedder!
I see you are following the post in grasses pastures board so you will see I am partial to my used NH316 square baler, but you may better steer clear of that if you don't like tinkering with knotters.( Although small squares will give those boys of yours strong backs big pipes without them messing with your gym gear!! :lol: ).
The haybine needs guards and sections with some regularity, but a monkey could do that. Changing the drive belt is another story, but it has only needed that twice in 5 years.( Got the time down to just over an hour last time, only a few bolts left over :lol: ).
Make sure parts are handy for whatever your gonna buy, because you will need them.
Excellent suggestion earlier about the owners manual. Maintain the equipment to the highest standard, and get it out early in the season to check it over and make sure it is put away clean.
Having a tedder has saved me a lot of hay. Not sure of your drying conditions.
For that size of field I would steer clear of disckbine unless you have a lot of gopher holes etc.. Make sure the conditioning rolls are straight on your haybine.
As with any machinery look for bends, cracks, welds, recent paint, and ask about it.
Size your machinery to your field and tractor.
Nice to see and hear something clicking over if you can before you buy. Chains and bearings on the baler. Net wrap sounds nice, never used it though. Depends on what you want to spend.
The main thing with getting your moneys worth out of the equipment is making great hay. May be easier said than done, depends on your conditions, but with your own stuff, you control whether that will happen to a greater degree.
Good Luck
ALX