How do I report my mystery shopping income in SE Turbo Tax?

I have a 9-5 job and as a side job, I mystery shop.  I'm considered an independent contractor and started about a year ago.  For all the companies that I mystery shop , none reached to $600 to entitle a 1099 form, but I had made over $1500.  My taxes used to be easy, but with this income, Turbo tax recommended to upgrade to self-employment.  First, the software asked several questions about my situation and when I responded to have other income question, it asked me if it was a side job or business (you click on the squares).  I chose "side job".  When I was done entering the W-2s from my hubby and mine, and went to the mystery shop income,  it asked about my mileage and other expenses (cellphone bills, car insurance, etc.).  Am I supposed to deduct a % of my cellphone, car insurance and internet bill as my expenses?  I don't think I will make an office deduction because I don't have a proper office (just the corner of my dining table), but I use ink to print guidelines and instructions, so that one cartridge I bought can be deducted?  The other question I have is about mileage.  Sometimes I will mystery shop after I leave my 9-5 job and the shops are not exactly on my way home.  Let's say I have to drive south, but where I need to go is SE.  Does this one count as deductible mileage for my mystery shop? and then after leaving the store, can I count the mileage to go home?  I know this sounds like double dipping and the least I want is to have issues with the IRS.  Please help me clarify doubts about deductions and mileage.