My wife and I have overhauled our personal budget to reflect the 'pay yourself first' approach (allocate in order: income comes in -> invest -> donate -> fixed expenses -> variable expenses -> fun $$).We are looking to see what experienced people generally recommend for a holding tank for that 'invest' allocation while we target our first real estate deal.What financial vehicles have you guys used that works well for this?

Price range seems to be so fluid from what I'm seeing - as I'm sure you well know this but a home in one town might be $20,000/$30,000 variation in another.

I own a home which I’m currently living in and planning on making a long-term rental property as well once I move out.

It's likely you'll be able to raise the rent as well with the upgraded unit and you can look to market it during the time of rehab. 

Didn't get into rentals on pupose but it's working out well and I want to continue to learn and develop my portfoilo.

Those remote flips and high cash flow rentals are so tempting on paper, but they rarely go well in reality. 

Class A properties will generally have high valuations and lower market Cap Rates.Class B Property:A step down from Class A, Class B properties are in the 10 to 20 year-old range, and are mostly well maintained.

If I could move to a more simple software than QBO, it would save me several thousand a year, and the simplicity would be valuable as well.

Class C is more work than class B, but if managed well can do great.  

An additional benefit of a detailed engineering-based Cost Segregation Study is that it can increase potential insurance premium savings as well as provide support for the property tax appeals process.