If you hire a PM, your financial account structure can be simpler.If you plan to continue purchasing rentals, I like some key accounts at the "management" level (income, opex, tax, owncp, reserve) and only have 1 checking account per property to prevent having 100 accounts and unnecessary complexity.

The more rehabs you do the better understanding you will have of the market for contacting work and materials.Doing a rehab every so often prevents you from being sharp with your budget.For those with limited exposure, ask others in the industry and always run your numbers based on being overbudget and overtime. 

It also prevents you from making the #1 noobie mistake, which is buying in the hood just because it's cheap.

Quote from @John Underwood: LOLI'm certain they will add restrictions to prevent people from doing this.

You can claim to be the best guy in the world at finding and analyzing deals, but when the market turns against you, and you just went all-in, even on the best relative opportunities that market had available at the time, there is nothing you can do to prevent losses, especially if your debt has a maturity date that will force your hand.Timing the market is an interesting concept. 

What prevents them from doing that?

I applied for a HELOC and when they ran the title it came up that the 8k grant is actually a second "soft" lien against my property that will go away after 5 years which prevents this bank from allowing me to have a HELOC.

Many people have limiting beliefs, a mental barrier that prevents someone from achieving their goals or living fully, so they sabotage any hopes of progress through words or actions.

I believe it tends to give me a slightly lower return, because the sponsor is going to be more careful, and if there is a severe downturn will prevent me from taking catastrophic losses.

A few clients or properties can suck up all of our time and attention and ultimately, prevent us from taking on more business.