They and their Realtor tell me it's a $150k renovation job based on rolling the dice or throwing darts at a dart board, or whatever it is people do to come up with these whimsical numbers.

The more time you allow into the equation, the more external factors pushing the risk higher.Thus - get out when the investment is maximized, but be prepared to stay for a decade if can't get out.

Find a good agent, I'd get coffee with a few, and then get the mortgage process rolling. 

Some landlords will push that and your local government should provide methods for auditing.A flat fee system is perfectly legal if written as such in your lease and it doesn't matter if the collections exceed the costs.  

I am going to be selling the house I used to live in, and I am hoping to roll that equity over into a new rental.  

As such, I am looking for references for a reputable company experienced in real estate IRA to roll a portion of my retirement account for use as liquid assets.

It would have a lot more equity in it now, but I am happy with the investment I rolled the equity into more.

All parties involved push on like a train down the tracks and just bear with it.

We were glad that we went with a smaller home knowing that if something catastrophic happened (*knock on wood*), we wouldn't be pushed into foreclosure. 

There's a big push in the region for walkability, so PG County with it's 15 WMATA stations and the upcoming Purple Line are worth exploring.