Private gender ultrasound??

So we’ve “known” that baby was a girl since our nuchal screening, the tech took some time at our request to try and see but we were obviously only 12 weeks so she could only be about 70% sure. Well at our 15 week ultrasound baby was being stubborn with its hands between its legs and we were able to tell. My next ultrasound isn’t until May 3rd, I’ll be 20 weeks on the dot. I really want to find out now, because it’s like we’ve “known” for a month now and I just want to be sure. Is it worth paying for a private ultrasound? A place around me will do one for $79, but my fiance isn’t necessarily okay paying that when we could just wait a month. But I don’t want to wait 😫 tell me its worth the money