Performingloans.com:
Positive
- online credit is popular, so if you find a good end user, you might get good value.
Negative
- other TLD's are avaliable, thats hurts the value
- as TA told you "Most of the matches for performing loans are coming from un-performing loans"
Value: high $xx
NiftyArt.com
Positive
- catchy name
- easy to pronounce and remember
Negative
- other TLD's are avaliable, thats hurts the value
- not a popular topic
- plural would be better
Value: low $xx
Estibot.com is a great tool, to analyse the domain, but as it says in the website:
"IMPORTANT: The purpose of Estibot.com is to give you keyword data and information about your domain. The dollar valuation is not to be taken literally - it may change, and it is only a quick-look measure of the keyword metrics.
Do not make a purchase or sale decision based on this appraisal"
If I were you I would take time here in Namepros, read and search to get knowledge before you buy anymore domains. We all have made mistake, I know I have

.
I must have the worst domains ever anyone has started out with
Here is some advise I got when I started out:
Generel
1. Make goals to where you see yourself in this domainbuisness in 1 year, 3 years, 5 years and 10 years. BE REALISTIC.
2. Split your domain investing in parts; for short time investment and long time investment.
3. If you dont plan to park the domains, make a website for each of your domains.
4. Make a plan for each of your domains. Park, minisite or unique site, decide before you buy the domain.
5. If you want to make a unique site, then develope a concept for the domain.
6. Market your domains through joining forums and smoothly drop in your links to your domains. This is the free mode style
7. As soon as you have bought each domain, submit your domain to Google, Yahoo and DMOZ, and all other search engines you can find.
Domains:
1. stick to .com, until you have experience.
2. No Numbers in domainname.
3. No Hyphens in domainname. Unless it is a very good domain.
4. MAYBE THE MOST IMPORTANT ADVISE, STAY AWAY FROM TRADEMARK DOMAINS!
5. Be sure that the domain, is REALLY pronounceable

6. If the .net and .org also are free, then take them too.
Good luck and best regards,