If you're set on a theatrical run, but no established distributor is picking up your film, then consider renting a theater.
In this case you'll become both the exhibitor and the distributor.
This means you'll have to aggressively market your screening 2-3 weeks before it plays.
A person not familiar with your movie at all will need about seven exposures to your advertising before they finally make the decision to come check out your movie.
So once you book the date(s), delegate the screening to someone else.
And focus heavily on the marketing.
If you ignore this, and don't aggressively market the movie's screening at least 2-3 weeks before it plays, you're unlikely to recoup the cost of renting the theater.
So consider, wisely, if you should proceed with a theatrical presentation.
Do the numbers.
If it's going to cost you more out-of-pocket, in the end, to play the movie... consider what immaterial benefits you may receive.
If there still aren't that many, and all that's left is a sense of "pride," consider doing something else for distribution.
This is the age of the Internet.
There are so many new options available.
I'm 100% convinced if the Internet was around when the Forty Thieves were conning audiences to watch their exploitation films, they'd ditch the cinema for online distribution ASAP.
And you can focus on marketing.
Even marketing is cheaper on the Internet... especially if you know what you're doing.
But if you believe you have a good shot of drawing large audiences to your DIY theatrical exhibition, using a combination of an alluring commercial film, innovative aggressive marketing, publicity stunts, and other popular draws of attention... GO FOR IT XD
Because although we're in the digital age, the novel real-life experience is forever.