I do think the application could be better and I wish it was more customizable.

I only build Wordpress sites due to the level of customizability as well as the SEO benefit (and the plugins).

Focus on getting leads.Podio is a great, free, customizable CRM.  

Flip houses too.Very powerful and customizable. 

It is very customizable and powerful.

I would say Elementor is one of the more powerful tools when it comes to built in functionality and customizability for a reasonable price.

Check out dealcheck.io for a much more robust and customizable option. 

If your not comfortable using it watch a couple of videos on how to do basic functions.I have over 20 properties and Excel makes it a snap to keep up with everything on a Dailey, monthly and annual basis for tax season.I keep additional data like AC filter size, trash day, Magistrate for each property, lease renewal date, occupants contact info, date of last inspection, date water heater or HVAC was replaced and so much more.It is very powerful and customizable.

Some property management apps have a focus on accounting (with customizable categories) and report generation so it sounds like that would be suitable for your needs.

The simplest model for this would be for you to create a customizable fund where you put all these deals and investors will have the ability to choose which house they want to invest in.