I get only 5 tests, conveniently I see that there are five possible lots to choose from in the ParkCalc UI. The requirements are also in a nice tidy group of 5. Clearly, this isn’t the only way to structure the tests, but as of right now it seems like a decent place to start based on the information I have. Since I’m limited to 5 tests, I want these to be powerful. By powerful, I mean I want each test to have the possibility to expose multiple issues, provide multiple types of information, and be representative of how a person might actually use the app (according to my imagination).

So here goes, here are my five tests

Valet Parking
Requirements:
$18 per day
$12 for five hours or less

Test values:
Start: 01:32am 01/09/2014
End: 06:32am 01/13/2014

Total time: 4 days 5 hours 0 minutes

Expectation: (18*4)+12 = $84
Result: $84

Some stuff I think this test tells us:
non-round numbers for time handled
$18 / day calculation
$12 / <= 5 hours calculation

Short-term hourly parking
Requirements:
$2.00 first hour; $1.00 each additional 1/2 hour
$24.00 daily maximum

Test values:
Start: 01:32am 01/09/2014
End: 04:17am 01/10/2014

Total time: 1 day 2 hours 45 minutes

Expectation: 24+2+2+1 = $29
Result = $30

This seems to have exposed a bug. I didn’t spend much time investigating what the bug is but I did notice that the cost of full days and 1/2 hours is not how it is described in the spec. In the app, a full day costs $26 and 1/2 hour (after the first hour) cost $2.

Some stuff I think this test tells us:
full day calc
first hour calc
additional 1/2 hour calc
info about rounding to 1/2 hour

Long-term garage parking
Requirements:
$2.00 per hour
$13.00 daily maximum
$78.00 per week (7th day free)

Test values:
Start: 1:32am 1/9/2014
End: 4:02am 1/17/2014

Total time: 8 days 2 hours 30 minutes

Expectation: 78 + 13 + 6 = $97
Result: 97

Some stuff I think this test tells us:
week calc
day calc
hour calc
info about rounding for times between one hour

Long Term Surface Parking
Requirements:
$2.00 per hour
$10.00 daily maximum
$60.00 per week (7th day free)

Test values:
Start: 1:32am 1/9/2014
End: 4:02am 1/17/2014

Total time: 8 days 2 hours 30 minutes

Expectation: 60 + 10 + 6 = $76
Result: $76

Some stuff I think this test tells us:

Economy lot parking
Requirements:
$2.00 per hour
$9.00 daily maximum
$54.00 per week (7th day free)

Test values:
Start: 1:32am 1/9/2014
End: 4:02am 1/17/2014

Total time: 8 days 2 hours 30 minutes

Expectation: 54 + 9 + 6 = $69
Result: $69

Some stuff I think this test tells us:
week calc
day calc
hour calc
info about rounding for times between one hour

Recap:
So, 5 tests and one bug was the outcome here. I’m pretty pleased about finding a bug of course but I’m not so sure I would call the software unfit for use because of this. I suppose that all depends on the person using the software. My opinion is that the difference in calculation is slight, and if the actual amount charged from the lot it correct, then it’s all good.

What skill(s) does this exercise help develop?
I’ll just make this a list of the stuff that jumps out at me:
domain testing
scenario testing
testing directed by a specific mission
note taking
thinking critically about how a bug affects a person(s) / thinking about value
describing the purpose(s) of a test
creating powerful tests