KDP categories · Top KDP authors
Charis StudyHall: Amazon KDP author data
As of Nov 6, 2026, Charis StudyHall has 21 books on Amazon, 16 of them on a best-seller list in the last 30 days (best rank #12), mostly in Water Supply & Land Use, Waste Management, Water Quality & Treatment.
| Median price | $22.99 |
|---|---|
| Price range (middle 50%) | $9.99 – $27.72 |
| Median reviews | 1 |
| Total reviews | 21 |
| New listings (30 days, incl. new editions) | 0 |
| Breakout books (30 days) | 0 |
What stands out
- 76% of the catalog made a best-seller list in the last 30 days: the whole backlist sells, not one hit.
Charis StudyHall's best-ranked books
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Illinois CDL Study Guide 2025-2026: Your Comprehensive State Commercial Driver’s License Exam Prep with Pre-Trip Inspection Scripts, Mnemonics, 1000+ Practice Test Questions and Answers Explanations
by Charis StudyHall
- Price$7.59
- Reviews-
-
Roofer Exam Study Guide: Your residential and commercial roofing Prep with safety review, simplified estimating, Repairs, 500+ practice questions with answer explanations
by Charis StudyHall
- Price$23.99
- Reviews-
-
Texas CDL Study Guide 2025-2026: Your Simple Prep to Ace the TX Commercial Driver's License Exam with Full DMV Rules, Tips, and Safety Tips Including 500+ Practice Questions and Explanations
by Charis StudyHall
- Price$8.99
- Rating5.0
- Reviews3
-
California Wastewater Grade 2 Exam Study Guide: Your Unofficial Prep for the SWRCB Treatment Plant Operator with Essential Math Formulas, 400+ Practice Questions and Answers Explanations
by Charis StudyHall
- Price$34.59
- Reviews-
-
California Wastewater Grade 3 and 4 Exam Study Guide: Your Simplified Treatment Plant Operator Prep with Advanced Math Breakdowns, Scenarios, and 600+ Practice Questions with Answer Explanations
by Charis StudyHall
- Price$34.59
- Rating4.0
- Reviews1
- Published2026-05
-
DANB RHS Study Guide 2026-2027: Your Simplified Radiation Health and Safety Exam Prep with 500+ Practice Questions, Answer Rationale, and Strategies to Ace Infection Control, Angulation, and Exposure
by Charis StudyHall
- Price$28.89
- Reviews-
-
Florida PERT Study Guide 2026-2027: Your Simplified Postsecondary Education Readiness Test Prep to Conquer math, reading, writing with 5 Full-Length Practice Exams and Answer Explanations
by Charis StudyHall
- Price$9.99
- Reviews-
-
California Wastewater Grade 3 and 4 Exam Study Guide: Your Simplified Treatment Plant Operator Prep with Advanced Math Breakdowns, Scenarios, and 600+ Practice Questions with Answer Explanations
by Charis StudyHall
- Price$9.99
- Rating4.0
- Reviews1
-
High Pressure Boilers Operator Study Guide 2026-2027: Your Simplified Exam Prep to Master Water Chemistry, Steam Calculations, and ASME Codes, with 600+ Practice Questions and Answer Rationale
by Charis StudyHall
- Price$9.99
- Rating5.0
- Reviews1
-
Roofer Exam Study Guide: Your residential and commercial roofing Prep with safety review, simplified estimating, Repairs, 500+ practice questions with answer explanations
by Charis StudyHall
- Price$9.99
- Reviews-
Main categories
FAQ
How many books does Charis StudyHall have on Amazon?
KDPTop tracks 21 of their books; 16 made an Amazon list in the last 30 days.
Which categories does Charis StudyHall publish in?
Their books chart most often in Water Supply & Land Use, Waste Management, Water Quality & Treatment.
How does Charis StudyHall price their books?
The median price is $22.99; half of the books cost $9.99–$27.72.
Has Charis StudyHall released new books recently?
0 new books in the last 30 days.
About this data
Data comes from KDPTop's daily crawl of Amazon's public Best Sellers pages; medians use the latest list. The opportunity score (0–100, higher is easier to enter) combines the review barrier, the share of low-review books, list turnover, new-release share and price.