It earns a great rate of return compared to a bank account and is fairly liquid.

Rates will range from Prime (currently at 7.5%) to Prime + 4% (11.5%).

Rates can be very similar to those of conventional financing (Fannie/Freddie - full doc loans that you will need to prove income to get), but typically a little higher than conventional financing. 2nd - Networking and partnerships! 

Here's the breakdown:Financing: We used a seller carry deal with 25% down ($100k), a 30-year term (balloon in 10 years), and a 4.68% interest rate.

Where in a standard market rate rental a stain like that could be handled when you get around to it and the rent would still be due.

In this case, your monthly payment with 20% down will have a good MARKET rate if your DTI works with a much lower month payment and no mortgage insurance(MI).

FInd a good old school General Contractor and forget these engineers.

They have a group of funding sources that will compete against each other, this helps keep the final interest rate within reason, and offer a partial refund if they are unable to secure financing. 

An interest rate that works for her. 

If your property management company is good and has built an internal maintenance team which has set rates and had strong relationship relationships with licensed contractor which should keep costs in control, you should never need to shop contractors on your own I wouldn't think.So in short, our policy is give us your preferred contractors upfront if you have them, but then we work all tickets to resolution including dispatch, and payment of invoices.This is of course for operational expenses.