Limit on BRRRR loans

[Blake Hrabal]

If you purchase a BRRRR, can you also execute on purchasing(financing) other properties in the mean time if you have the capital to start planting seeds?

and if so, eventually mortgage lenders will begin denying you because of too much debt. At what point is that? x amount of properties...

any way around that; gotta be good friends with an underwriter? Or is it, you have to wait it out til you pay down some debt before you can purchase more. Would they still finance a flip at that point or complete rejection?

And while I'm on the topic, I've read you have to prove you have tenants ready to move into the BRRRR after rehab is complete in order to get approved for the loan....True or False?