If i wanted to rank for something like "buying used piano" but all my anchor text linking back to my site is "buyingused" then how many more links would i need? Like.. if i was using "buying used" to rank for "buying used piano"... how many more percent roughly, links would i need to rank for it? 10 x "buying used piano" means i would need 20x "buying used" to rank for it? any insight would be appreciated
There are a lot of variables that determine that factor. I'd recommend though getting about 70% incoming links with anchor text "piano" and the remaining 30% "buying used piano". As for how many...I'd say based on no other data you provided, 100 links.
I'd suggest that you use the Anchor Text Backlink Checker Tool to analyze the first 4 - 5 websites which are rankking high on Google for the keyword 'buying used piano' and 'buy used piano' etc. Once the tool is finished making a report for 1 site, click on the button for 'Summary of Report' at the end of the page. You should see a report summary with the anchor texts and number of times the keywords have been used in those Anchor Texts. Do this several times for different competitors, note down their results and see how many times they use those anchor texts in their back links. Your target should be as many links as given by the reports, if not more.
if it is possible to edit your backlinks to 'buy used piano' ,, do so... and just continue to build links with your new targeted keywords... im sure it can't really affect your backlinks...