be very careful, with home office write offs

Tax Id number is easy to get a the revenue office yourself or off their website, if you don't need to buy wholesale you should not need it, your social security number will be all that is required for Sole proprietor (I think) if you don't need to purchase equitment and supplies wholesale but, just need to file sales and use tax quarterly

EIN, is only for LLC and such or if you have people working for you (I think)

not sure if you need it for a S-corp, I'd have to check

first you need to go file your DBA form but, You probably are already aware of this,since the bank won't usually open a business account without it