It's completely depends on your travel partners and how many days you will be there.
Normally Hotel Cost 1300/- per day(Average Hotels). You can book hotels via MMT. Kasol to Tosh Travel cost 400/- per head (Sharing Basis)
Foods are little bit costly. And Most importantly don't book your tour package via any Travel Agents..
Right, you can take these type of package from travel agents but if you want cover all the major places their and attend parties and festivals their. For that i can give one contact of a travel agent who mostly plan these types of packages and take people with them.
If food and travel is included for all the days then this package is perfect.
Otherwise it will cost a lot more than this as the public transport is very poor in this region and private Transport cost a lot.