This is actually pretty decent money for a 23 year old in a small town in North Carolina. Starting over from scratch you will not be making this NET salary. It will take a person some time to build a large enough customer base in a bigger city to meet or beat what you are making now.
Adding window cleaning as a part-time gig to supplement your income? Perhaps it could earn you up to a few hundred dollars. What hours do you actually have available from your regular job and life in general?
This is where reality meets the road:
Take a sheet of paper and make it into a time sheet for the next several weeks; Start time for you present job and stop times. Also enter in start and stop times AVAILABLE for your window cleaning venture. Allow realistic time to get from job A to job B. (Has the sun gone down yet?) Does that even look practical for you?
Tools:
Just do a general web search of anywhere to have 3 or 4 different size squeegee channels and rubbers, pole, bucket(s), scrubbers, white pads, fine steel wool, ladders, towels, gloves for winter, soap, razors and blade holder, insurance, work shoes (they wear out faster than you expect), marketing budget, invoice or receipt book, CPA, vehicle maintenance. Put some real dollar figures next those listed on your paper.
As a part-time gig it will be daunting to make headway; it might be better to repair and upholster furniture at your home as you have experience in a good paying venture already.
$80,000 NET is a long shot in a business that you have no knowledge about. Sorry.