I've been pretty lucky in that I've had good rooms to deal with.
Top things to avoid are-
1-setting unrealistic goals
2-Not learning to be satisfied
3-Spend $50,000 to listen to $1,000 of music
4-Trust others ears over your own
5-Thinking 20 watts is enough for your power hungry speakers
6-Thinking tube watts are more powerful than SS watts
7-Being an early adoptor of new technology
8-Buying anything with the word "magic" in either the product name or company name
9- Buying any gear that relies on mystery technology or a mystery explanation
10- Audition equipment with unfamiliar music
Top things to avoid are-
1-setting unrealistic goals
2-Not learning to be satisfied
3-Spend $50,000 to listen to $1,000 of music
4-Trust others ears over your own
5-Thinking 20 watts is enough for your power hungry speakers
6-Thinking tube watts are more powerful than SS watts
7-Being an early adoptor of new technology
8-Buying anything with the word "magic" in either the product name or company name
9- Buying any gear that relies on mystery technology or a mystery explanation
10- Audition equipment with unfamiliar music