How much it would cost yearly to mow a 50 acre lawn (by yourself or hire someone permanently) and what machinery should be used to cut grass to 2 inches once a week? 10 acres an hour should do the job quicker.
This will be a rough estimation; 3 mowers, 36" wide, stand to ride, 1 mower = 2 acres per hour, gas, oil, dump fees for clean green, aeration once per year; 2 plug aerators 2 operators = 4 hours, maintenance on mowers and blowers and trimmers = 3 hours per year, fertilizer @ 4X per year for 10 acres. 8 months. Cool season grasses. These numbers are for 10 acres.
Mowing once per week for 8 months $ 9,216.00
Fertilizer 4X per season approx. 44# NPK X 4 X 5.00 = $844 plus labor = $ 1044
Dump fees; $250
Plug aeration: 2 rentals at $150 2 guys @ $40 per hour 10 acres = 6 hours $ 630
Blowing out irrigation once per year; $ 550
Restarting irrigation in spring: no charge
Monitoring water schedule to train grass roots per season; $ 225
Maintenance equipment: $550
Total for 10 acres; $12,465 x 5 = $62,325 for 50 acres per year.
Again, this is rough but no small change.
In general, the more capital you can apply to the work the higher your labour cost per hour will be but the faster the job can be done and the higher the quality. I suggest that first consider what quality you want from the appearance. Using the term "lawn" implies a high quality, smooth and uniformly green. The term "grass" is a bit looser; up to you which you continue to use.
For capital equipment for that area you are probably looking at a tractor mounted implement of some kind. There is a single pull behind rotary mower, a box flail or a sickle bar mower. The quality will be rough, but the capital expense will be lower. Better is pulling multiple smaller rotary units behind. There is also a tractor mounted gang reel mower which does a higher quality job and will be quite fast.
A quick image search on "tractor mounted gang mowers" might help. A good step in getting information would be to talk to local golf course maintenance staff or local authority roads and parks people. Don't hesitate to contact a local landscaper and ask if they have a tractor mounted mower and get an estimate.