Anyway it's very hard to do anything out of the ordinary in Irvine, if ever there were a Stepford community, that's it.

The current patio and walkways around the house are all concrete, but look a little rough and are all mismatched, so I'd like to replace them.I want it to look nice since I'm spending a lot of money ($100k) renovating the rest of the house, but I also know tenants with kids can absolutely destroy pavers with their bikes and toys -- so I'm a little torn.Should I install pavers or just use concrete for the patio and walkway?

The amounts not treated as return of capital will be treated as unrecaputred 1250 gain (taxed at ordinary rates with max of 25%) until all depreciation has been recaptured. 

You must also claim $75,000 of ordinary income on top of anything else you already earn.

So far I've had to replace all windows and a patio door in just 1 building.

How not to deal with them just like ordinary tenants by screening, credit checking, etc...

In terms of your experience thus far, just know much of your experience is not out of the ordinary.

New siding, a new cement patio and walkway, new flooring, remodeled the 2 bathrooms and painted in and out.

As you accumulate wealth its much easier to bifurcate it and invest the "cash" in depreciating assets and retirement funds in things like notes/lending etc. which are typically taxed at ordinary income.

Money on this spec is short term-ordinary income....