575's really hold their value. I sold mine for what I paid for it actually and no quibbling either. Sold it on Tractor House in 3 days. Mine had all the options, hydraulic tongue swing, extra sweep pickup and knotter blowers as well. Always kept inside too. I keep all my tractors and hay tools inside all year.
I will warn you about one thing and that is, if you are selling small squares to horsey people, be very careful about how much preservative you apply because it will impart a chemical smell to the hay if over applied and horsey people have good smellers. Myself, I'd never bale at 20% relative and my 575 as well as my round bailer has/have the Delmhorst slipper shoes in the bale chamber and feed table that gives me an ongoing and continuous moisture reading to the digital readout in the cab plus I can set the maximum relative moisture to whatever value I want and it will alarm if I go over that preset number. Delmhorst moisture meters are not cheap but Delmhorst is the recognized leader in moisture monitoring, plus I can unplug mine and use it to check the moisture of windrows or take a sample of forage and put in a plastic bucket and probe it for RM as well.
One thing I believe in and that is, you have to invest in the necessary tools to make sure your crop isn't going to spoil. Good rule of thumb for me as far as RM is concerned besides the Delmhorst is, I watch the bailer as I'm bailing and if it's producing at least some chaff, it should be ok far as moisture content. That don't apply to bailing wheat straw however and I only bale wheat straw after it's been rained on because the rain washes off the wax coating and makes the wheat straw much more absorbent for animal bedding. I used to square bale entire wheat fields for the local road board. Talk about a boring job, but it paid really well and it was no touch as well. Their employees picked them up and hauled them away. All I ever did was keep the twine box full and drive. I believe the most I ever ran in one day was 4200 squares and that was from dawn until dark, just stopping the replenish the twine balls and take a leak and eat a sandwich which I did on the fly. I charged them 35 cents a bale so you do the math. My big issue with the 575 was how it tossed me around when making headland turns. That packer box had a ton of inertia even with my heavy tractors. I don't miss any of it in reality. Computer driven round baling for me is light years easier and all I have to do is change net rolls infrequently. Everything from bale density to number of wraps of net is computer controlled, I just watch the screen in the cab to make sure I'm evenly filling the bale chamber and the machine tells me when it's time to eject a bale and rounds are so much less labor for me plus I don't have to find help to load the barn loft anymore either.
Small squares to me are a ton of work for not a lot of financial reward for the work done and I have only one customer and he buys all of it and has for over 5 years now. he drops his semi trailers, I load them, he secures them and off they go.
Right now he's lusting for my alfalfa second cut. I had rain issues this year and was unable to get an early first so it will only be 2 cuts this year unless I do a winter cut, which I may depending on how it grows. I've harvested my best hay in December and even January here. So long as there is no snow on it, it dries down fine.
Alfalfa is touchy anyway. I cut it using the wide thin swath attachment on my discbine and then let sit for a couple days and then windrow it with my Kuhn Masterdrive twin head rotary rake, let it sit another day and bale it up. I do it entirely by myself and I'm 74. The issue with alfalfa is, the more you disturb it by raking or tedding, the more it suffers from leaf loss. I have a 4 star tedder as well that never leaves the barn. I should sell it as I never use it and I bought it new.
