Good recommendations.
Here are a few more:
1) if building new and there’s not enough slope on the lot to incorporate a walk out basement door extend the foundation walls and build a set of exterior walk down basement stairs.
2) if possible install two sump pump pits and two electric pumps(when one of them fails in 5-10 years the other will still function) in addition to a water pressure powered or heavy duty Marine/RV battery back up sump pump.
3) get a natural gas auto generator or at least a small gasoline generator to power the pumps during an extended power outage.
4) make sure you have a sump pump rider on your homeowner insurance policy. I pay $60 a year for $15,000 coverage. If you don’t have one they will give you $0.

3BA0747F-FD50-4EA5-ABE7-40A140ACD268 (resized).png

D44B8C00-72EC-468F-8E9E-C7401AEF7F59 (resized).png

Surprisingly the cost of a square foot of unfinished basement area is less than half the cost of one square foot of living space above it.
As others stated winter frost is a huge consideration.
Also comfort is a huge factor. Spend 8 hours standing on a concrete floor vs the same amount of time on a subfloor built over a foundation or crawl space. My knees and ankles hurt after a few hours of standing/working on a concrete floor.

Walk out basements are a dream come true for most pinball and arcade collectors,
Especially if there is a turn in the basement stairs!
Just make sure that you install a French door and not a sliding door so both panels open to give you a full 6 ft opening.

2637C3DE-0726-4D7E-83E0-03FC451C86F0 (resized).png

656D4F89-8516-403A-B1C8-7561F70D449A (resized).png

I forgot to say if you only have one sump pit
Buy an extra pump and prep it so it can be swapped out very quickly in case of a failure during a big storm.

You are correct a piece of stone/Gravel or a stone chip can jam the pump impeller and render it useless.

I recommend anyone who has a sump pump keeping a basement with machines in it dry to get a pair of thick rubber elbow length gloves and clean out their sump pit to ensure there’s no stone or debris present. I’ve seen new or newer homes with a few inches of mud/stone that got knocked in during construction.

In my area perk tests are normally only done if installing a septic system. A backhoe digs a small hole and a specific amount of water is then added. Then they time how long it takes the water to drain into the surrounding soils.

My buddy sent me a pic of a bathroom he used in India. It looked like a strange combination of a shower and a urinal that was mounted flush with the floor that you squatted over. It appeared the only way to use it would be to completely remove your pants and underwear.