New boss had me start work before I was on payroll, I don’t think she has any intention to pay me

Location: Missouri

I just started working at a small business in St. Louis run by one woman in her mid 80s. She is the sole owner and the only other staff are part time employees on the same level as me. I thought something was fishy when I first started and only signed one document that said I was being offered the position to work x amount of hours a week and had to give a week’s notice before taking time off— it mentioned no pay rate or timing of pay, but she told me in the interview she’d pay me 17/hr and I’d get paid monthly. I’m in the middle of my third week and she refuses to get me on payroll until the END of this month, as she says the firm she uses “won’t care about any paperwork turned in until it’s time for them to process pay.” That sounded like BS, so I insisted she get me the correct forms to sign, she claims she called the firm yesterday and that the forms are “in the mail.” I have no idea what these forms even are so I can’t just print tbem out myself (as she’s told me to do multiple times if I’m so worried about it. Which of course I am.) She also told me because I only worked a few days at the end of last month she’d pay me with a personal check for June instead of through payroll so I “wouldn’t get taxed,” but I’m a freelancer for a couple odd jobs and I’m already going to be paying self employment taxes which are much higher (as far as I understand) on anything else I earn this year that’s not through payroll.

She has us write down our hours on paper calendars which apparently she mails to the payroll company at the end of each month. An employee who’s been there a few months told me she does pay eventually, it just takes a while. She’s also spent significant time complaining about how she’s broke and the company costs x amount to run each month, implying that she struggles to cover all the expenses (including payroll) and sending me on errands to buy things for tbe office with a handful of credit cards- as it often takes several tries for one to go through without being declined. She’s also very elderly and forgetful and doesnt seem to have any idea what the onboarding process is- and has in fact insisted several times that we already got all the paperwork taken care of, which we certainly have not. I’ve been patient in re-explaining it several times and she’s only gotten more frustrated and insists I’m being unreasonable.

Today my plan is to go in and insist I get those payroll forms either emailed to me or that I drive to her payroll firm in town and pick them up myself. I want to insist I won’t work another minute until I have some kind of written confirmation that I’ll be paid at the hourly rate we agreed upon. I want to have confirmation from whoever this firm is that I’m being onboarded and I want to be paid through payroll for the few hours I worked in June AND what Ive worked so far in July. I’m fine waiting til next month for that July check- I just need confirmation that it’s coming. I’ve already resigned and my last day is the 25th, but I need to get paid for the hours I’ve already worked even if I walk out today. I’d like to continue working through this month as I need the money, but only if I know I’ll be paid for it.

Do I have any legal standing if she refuses to onboard me or refuses to pay me outright? She owes me close to 700 dollars and a friend of mine told me to ask her to pay me the difference in self employment vs. income tax if she just wants to cut me a check and be done with me today (which I think at a minimum is about 10%). I’m really not sure what to do or what my rights are here, and I’m afraid this is going to screw over my taxes. There’s no way this lady remembers to send our W2s at the end of the year. I dont want to take this to small claims court, but I’m afraid it might go that way.

Any advice or facts I should be aware of?