Welcome
It is not a get rich quick adventure nor can most people make a full time living. Some of us/them do a LOT and some do a few a month.
Reimbursement is not always the full amount, pretty close most of the time but not always 100%. Some do pay a report fee, some do not so then you only get free food,etc.
You do buy with your money first .... some pay back within days (rare) and some you have a wait time for several weeks or months.
Profit... it is your call..... it is a job to be taken seriously but if you are working this for decent money you need another job too!