I've read both and they're excellent reads to get started.

Is there a database/excel sheet/rule of thumb list I can use? 

If their quality of work is similar go with the 1st bid bid and don't look back, $1500 is a big difference.

It depends on what it needs and what the marketplace expects as far as quality of property.Personally if the place is empty when I get it Like to rehab to a nice level for two reasons.

Crime, homeownership %, the possibility of appreciation (because of the demand from homeowners), are factors that attract quality tenants.

Just remember, repairs of roof etc will be needed down the road unless in excellent condition.

Since you already own the property in your IRA, it is a given that you need to hire a property manager, people to do repairs, and you'll need to have the custodian handle all contracts and money in/out.Generally the question of whether to do long term rental or short term rental has to do with the location, quality of house, local rental regulations, typical nightly price, expected annual occupancy rate, availability of short term rental property managers, etc etc etc.

Are their listings detailed with good quality photos?

I imagine if you leverage the location of your property correctly, you can see excellent cashflow from rentals or AirBnB. 

Mentors value your efforts to give first, as this is the fundamental of creating high quality relationships with people.