StyleCop is free. The development is done in spare time and weekends.
Install order should be :
This version is now compatible with R# 5.1 (5.1.3000.12), R# 6.0 (6.0.2202.688), R# 6.1 (126.96.36.199), R# 6.1.1 (6.1.1000.82), R# 7.0.1 (7.0.1098.2760), R# 7.1.1 (7.1.3000.2254) and R# 8.1 (188.8.131.526).
Here are the bug details for fixed in 4.7
and closed in 4.7
issues (over 200 issues fixed since 4.6)
Here are the bug details for all issues since 184.108.40.206 that have been fixed
(over 650 fixes).
Updated Release Notes are available here
Online Rules documentation is available here
Older versions of StyleCop are available here