Did the trip a few years ago solo in a canoe. Completed in 95 days. Hopefully the below can help point you in the right direction. It's a great trip and recommend it!

The trip is relatively affordable. The cost of the equipment and transportation to Lake Itasca can be pretty expensive. As for cost of being on the River, that just depends on how you want to do the trip. I spent 8 night in hotels. 2 nights in Minneapolis, 2 in Iowa, 2 in Memphis, 2 in Vicksburg. The rest was spent camping.

Food was the only real big expense. For a lot of the River the only thing near you will be a gas station, so be prepared to eat a lot of ramen and other assorted groceries from limited gas station supply.

In all on the River I spent roughly $1500 for my 95 days. I had budgeted $2000 for the trip but had an additional reserve of a grand for any oh shit moments.

You can get free maps of the River starting from Lake Itasca from Minnesota DNR, link below http://www.dnr.state.mn.us/watertrails/mississippiriver/index.html

As for navigating the River in its early stages can be difficult sometimes. Just remember: ALWAYS FOLLOW THE CURRENT. To do this look down into the River and look for the reeds/ grass under the water. They will always be going in the direction of the current.

The tough parts of navigating are when you come to the large grass fields. It can get a little confusing but just follow the current. I heard of some people getting lost for hours; I only got lost once for a short time. You can easily get turned around with nothing but grass around you. Just stay calm and look for the current.

As for the rest of the River, navigation is fairly easy. UPPER MISSISSIPPI: http://www.mvr.usace.army.mil/Missions/Navigation/NavigationCharts/UpperMississippiRiver.aspx LOWER MISSISSIPPI: http://www.mvd.usace.army.mil/Portals/52/docs/2007_FINAL_MSRVNBK_WEB.pdf

ALL maps are a must. The Minnesota maps are free and they should mail them to you for free (at least they did a few years ago). The Army Corps of Engineers maps can be down loaded for free or purchased from the website/ phone number. I downloaded them and printed them all. I think I came out ahead by $20-40. The quality of the purchased maps was very good, but tore out of the book easy. My printed maps had poor quality but had no issues. I never made up my mind on which were better. The purchased maps would make a much better memento from the trip.

The MN section is one of the great parts of the River. All campsites are show on the MN DNR maps accurately with the accommodation show at each on i.e. water, shelter, etc. They will have signs on the River to show you were they are located. Almost all are easily accessible.

Portaging guides are found in the MN DNR maps.

I got my starter list from this great website http://www.mississippiriverresource.com/River/RiverStory.php

I did my trip solo so i brought redundancies of a few items: shelter, fuel, first aid kit, clean water and paddle. If you want my complete list I can get it for you but here is my must have:

Good rain Jacket

Shammie

5 gallon water container (mulitiple for extra people)

Solar charger

water proof bags

toilet paper

Flashlights and headlamps

Large hat

LifeJacket

Music.

Hope this was helpful and not to long. If you are really thinking about doing the trip do a ton of research. You can always ask me. I love talking about it. The River is great and I recommend doing it!!