Do good work and always ask your clients for referrals, I use to give them discounts for referrals who hired me.  

If you buy low but then the rehab brings you up to ARV you didn't buy at a discount, and that's crucial.  

What is the usual discount for lumber, cabinets, shingles, plumbing, and electrical?

Therefore they tend to price at retail and you want buy at a discount.  

And if you did, where did you goto and what kind of discount did you get on the material?

These are people with deep pockets, who can weather the storm pretty well. 

My main concern with that is that's really diving in the deep end on renting!

I seriously doubt you will find a long-term lender who will take that deal at an interest rate that will work unless you're buying at a huge discount. 

Something dirty, smelly, dated finishes, awful colors, but all the major systems are basically sound, and discounted appropriately (or better) for the condition it is in ... don't buy it if they are trying to comp it based on turnkey ready homes. 

I expect listing agents to be far more knowledgeable and skilled in their market and pricing to be able to accurately price a property - heck if i can after watching the local market for 6 months they should - I asked a well known agency for a price evaluation they gave me a 2 inch thick binder and stated X amount - I said nope it's worth more and went with a discount broker and sold it for 25k more.