I have done a similar trip a couple of weeks ago, but on public transport. Went to Hyderabad on train and then started from there. Visited Bhit Shah, Sehwan, Sukkur, Ranipur, Khairpur, and Multan in 3 days.
Spent the nights at Sehwan, Sukkur, and Multan, day-stay at a hotel in Hyderabad.
Road conditions are mostly OK, with a few patches under repairs. BTW, it took about 4 hours from Hyderabad to Sehwan.
For safety, avoid road travel after sundown (specially around Dadu-Moro area).
Budget accommodation in Hyderabad: Hotel Paradise (near Railway Station): Phone: 022-2731772
Plenty of hotels/rest-houses in Sehwan (ranging 500-2000 per day). Sehwan Divine is a bit expensive. Stayed at Babar Guest House at Sehwan Sharif (3 minutes walk from Shahbaz Qalandar shrine): Phone: 0301-3584954
Stayed at Tourist Lodge Guest House in Sukkur - decent: Phone: 071-5805167
Weather pleasant.
Good luck with your trip.