Conversely I can see were this would be a default upgrade where all it's competition has nicer interior doors.It's the grey area that I'm wondering about.

I found something I could do immediately -- upgrade to Pro status!

I retrained my tenant by getting it fixed and letting her know that she was responsible for the expense, so next time she will consciously think "I wonder if this should go in the disposal...maybe not" because it is now her expense not yours otherwise why not keep doing it.You said the washer/dryer hose came off, did you move the washer/dryer around and knock it loose...no the tenant did.The breaker/fuse tripped so someone overloaded the circuit, did you plug the hairdryer, fan, laptop, tv and sound system into one plug....no the tenant did.The sink got clogged, did you pour bacon grease/mud/potato peels down the drain...no the tenant did.I say all of this because the tenant has no reason to try to make sure they don't cause damage because they will just get it fixed free.

Zig's quote is foundational principle of my real estate investing, but I'm thinking of upgrading now.What do you think?

.$100 per sq. ft quoted without any upgrades sounds high.

He used it to drive his clients around town and the IRS allowed him to deduct the cost of the upgrades.3.A couple hired a babysitter so they could do charitable work.

Another plus, is that the tenant would have a big investment in the way of equipment, and tenant upgrades meaning less likely to walk away from their lease.

(owner dumping becuase expensive upgrades needed)Is something changing that could affect the value?

No upgrades after the fact.I would only entertain some upgrades after a year if they've been good tenants and are renewing for another year.

The small, or basic, level is the property without any upgrades.