Real Estate Professional no W-2 and IRA contributions

[John Underwood]

I have no W-2 job, can I still contribute to my E*TRADE Roth IRA account

Situation:

I self-manage my LTR portfolio

I self-manage my STR property that is an hour away.

I buy tax liens at auction every year.

I have flipped at least one property per year, but not sure that will happen every year.

I am a RE professional 

I also have a Solo401k, but I only contribute to it prom proceeds of a flip.

So can I still contribute to a standard Roth IRA without a w-2 job?