Okay, so in a wild concept of actually returning to the original questions
I'm an editor, so I don't have that cost. However, here's a thought ...
Why do you need editing? How often have you written a book in, say, six months, then pored over it for another six months or more agonising about every detail. Yes, we'll shuffle all the commas around and fix stuff, but we can also help with closure of manuscript and confidence on the writer's part that it's ready for the world. My fee is on average US$100 per 10k words, so your "normal" book of around 50,000 words (to rate as a "book" in some sites) will cost you $500. Will you recoup that? Well, unless you're a strict hobbyist writer who doesn't care for sales, you should at least be hoping to aim for that.
I've designed many of my own covers using stock photos that aren't expensive, but avoiding some kind of pesky subscription to access them can be annoying. The software skills for the design aren't hard — they're the pretty basic elements of the software, so don't be overwhelmed by YouTube videos and what it can do, just worry about what you need. Otherwise, I've spent $200 on a professional book cover designer who is savvy about what the genre demands. Or you might need specific imagery, such as Tim's books, which will hard to source. But as someone said, spending upwards of this on bespoke images and hand-drawn covers is hard to justify.
How much are you willing to spend on advertising? That's not the question. It's how much you're willing to gamble on experimenting to see if you can make ads work. Starting budgets can be small on FB (I've never made AMS work). You could dedicate $150 a month at $5 per day to see if your ad is working — but really, 10 days is long enough, and remember that if your ad is set up properly but totally fails, it won't cost a thing. It's when authors leave the door open for FB to farm clicks that won't result in sales that you can waste money.
The aim is the achieve a positive ROI no matter how small, and things like book length (in KU) and pricing need to be considered, then you decide how far you want to push that envelope in regards to budget.
I spend about US$300-350 a month and get sales of around US$550-600. BUT I'm Australian and the exchange rate almost doubles that ROI. I started out at five bucks a day.
So advertising costs aren't really a problem as long as you have that positive ROI (and hold your nerve...)
Oh ... formatting. The Styles feature in Word will achieve everything you need for straightforward fiction.