Supposing no upgrades need to occur with my homes main panel, what is a fair appraisal of how much it would cost to add a 220 outlet and breaker for a dryer and a few 120 outlets for a home office? Attic and basement are open and unfinished, so access shouldn't be too much of an issue.
Also, if I do need to upgrade from 100amp to 200amp, what is an average of how much that might run? I live in SC. Thanks for your help in advance.

With different market areas, large and small contractors, and material cost soaring, prices are too difficult to pin point, unless someone here is from your area.Labor costs can be about $50/hr, so a day's work for one man will cost $400.00 plus materials, plus markup and taxes.

Using different materials, such as Romex with plastic boxes instead of MC and metal can be cheaper. Using aluminum wire for a service will be cheaper than using copper for the larger wires.

The outlets may be in the $600.00-$800.00 range, depending on length of cables and quantities of outlets. A 200 amp service can be from $1000 to $2000, and depending on labor costs and length and type of materials.