First of all I think it's unrealistic to think you could gross more than 10k in a month. If you worked the East Coast real hard you might take in 8k. Your cost per mile ratio would be pretty good figuring your DH miles would be low in the East. The hours of service rule is hard on single drivers so you would have to be very smart about what loads you take. You are looking at about 25% for fuel if you have and use an APU while sitting. Many East coast states have idling laws too. You will also have months when you will only do 5k per month. I would not recommend running solo. You need to maximize your equipment by running a team in your truck.
Signed on three "D" units with Load 1 in May of this year. All three are solo. Using 5/18 through 8/18 for a time period the trucks grossed the following:
Truck 1 $34,530.77 or $11,516.92 per month.
Downtime 10 days
Truck 2 $24,876.38 or $8,292.13 per month.
Downtime 17 days
Truck 3 $23,272.87 or $7,757.62 per month
Downtime 20 days
Running solo at Load 1 isn't a problem.