5 acres is tough to pencil out - but it can be done.
If you assume you are going to hay 4 of the 5 acres and buy used equipment.
We bought a New Holland 68, JD350 hay rake, MF32 sickle mower and 50 gallon sprayer for $1,750. All of these pieces of equipment worked out of the gate and we made some 1,200 bales the same year. Junk hay, but what we made in that first year easily paid for the equipment. We later added added a cheap tedder and haybine. The baler got refurbished and a 2nd baler was added - but now are doing more acreage, horse hay and need conditioning and reliability on the baling side. Flip side is our hay price has gone up too. We also had an old wagon we refurb'd - which we pull behind the baler and added two more, but again we have more acres than you and more bales.
Sooooo - if you have 4 acres x 100 bales per acre x $4 per bale and you are at $1,600 in total cash collected. You've essentially paid for your first pieces of equipment - AND you can get better equipment cheaper than we did if you can wait and/or are lucky.
However, be prepared to turn a wrench and have unexpected breakdowns. Haying ain't for the faint of heart, but when the field is cleared and the squares are in the barn - it's a GREAT feeling.
In addition to this forum, and Haytalk, there is also yesterdays tractors. Between these 3 forums, I doubt you couldn't get an answer to any hay equipment or haying question.
Here is our 1958 year model New Holland 68 and 1962 Massey Ferguson model 50 diesel at work earlier this summer.
New Holland 68 and Massey Ferguson 5 Diesel Baling Hay - YouTube
Good luck,
Bill