Does this kit work with other DeWalt 20V MAX batteries?

Yes. All four tools run on the 20V MAX platform, so larger 4Ah and 5Ah packs fit and extend runtime.

Is the drill powerful enough for deck building?

It is a compact drill/driver aimed at drilling and driving in wood and metal. For heavy auger bits or continuous deck work, a larger hammer drill is a better match.

What comes in the box?

The drill/driver, impact driver, one-handed reciprocating saw, oscillating multi-tool, two 20V MAX 2Ah batteries, a charger and a contractor bag.

Can the reciprocating saw cut metal and PVC?

Yes, with the right blade. Its 5/8 in. stroke suits light pipe, PVC and demolition work rather than heavy timber.

Do the tools have brushless motors?

The impact driver is listed with a brushless motor. Check each tool's spec if brushless matters for all four.

Is this kit a good start for a homeowner?

It covers drilling, driving, sawing and detail cutting on one battery system, which makes it a practical first kit. Add a circular saw later if you cut a lot of lumber.