So - yes, please share your experiences focusing on the places you overnight, cost and nutrition?
For got I had this photo from the Spearfish municipal campground:https://www.flickr.com/photos/105349603@N05/19293357935/in/album-72157655263744881/
Tranquil and immaculate. $20, but worth the price of admission:http://www.cityofspearfish.com/departments/city_campground/index.php
Will you be cooking or eating out. For various reasons, I did not bring cooking gear on my Black Hills trip. I missed it. There is a lot of meaty and fatty restaurant fare in SD. They seem to like ranch dressing on a lot of things, including the peas in the salad bar. When I did a Needles Highway loop out of Custer I found a place that had spinach salad with goat cheese and strawberries. I nearly fainted.
BTW...If you are not in any hurry and want to do the entire Mickelson, you could finish it in Edgemont, where there is a municipal campground at the south end of town with showers for $10/night. From there, you could take the old highway 18 to where it intersects with the current U.S. 18 and then take that to Hot Springs. It would be short day and leave you plenty of time to visit the mammoth site. That's what I did. Here is the route:https://ridewithgps.com/routes/8789349
The old highway was nearly deserted. At just past mile 8 you will see that it crosses the trail. That crossing is not at grade but rather via
a bridge high above the trail. The crossing just before mile 17 is at grade. If you use the Street View option you can see one of the numerous trail shelters off by the tree. That one has a water cistern as several others do. One issue with staying in Edgemont is the frequent train noise, mostly from 150 car unit coal trains with locomotives on both ends. I recommend ear plugs. Also, the grocery store closes at around 5 p.m. and is not open Sunday and is at least one of the two town's real restaurants. I would avoid staying there Sunday you might end up eating from the Sinclair gas station, which makes food 24/7.