KitKhat wrote:So I'm a recent grad of a year with a fairly good credit score 780's
Where is this score from? What scoring model? Which CRA?
Keep in mind that you don't have just one score. There are many FICO models used by creditors. For most you have a score with each of the 3 major CRA's. Always consider both the scoring model and CRA when referencing scores. Also consider the relevance of a model/CRA combo to a given creditor. For example, a TU FICO 8 isn't going to matter to a creditor that uses an EX FICO 8 Bankcard or any model/CRA combo that is not EX and FICO 8 Bankcard.
KitKhat wrote:I have a job and can easily pay the monthly expenses but I'm worried that by opening this card (Line of credit) that it will hurt my score?
I'm hoping to buy a home sometime in 2017 and just want to make wise choices now before my credit is ruined!
We'd really need a better idea of your credit profile to give meaningful feedback. Impact is never just about an a change by itself but one's credit profile and the how the details of the change would impact that credit profile. Person A could be intending to buy a home in 2017 and get the Best Buy card with little to no impact. Person B could also be intending to buy a home in 2017 and get the Best Buy card with a bigger impact. Odds are that even in the latter case the impact from the new account would be reduced and maybe even recovered by the time that person applied for a mortgage.
As stated above, if you have thin profile you'll want to put in the work right now to thicken and build that profile. To assess that we need an understanding of the number, types and ages of your credit accounts as indicated on your reports. If you're not regularly pulling and reviewing your reports then get started on that right now.
KitKhat wrote:Is it worth financing the item or just waiting till I can straight out buy it?
Worth is always highly subjective regardless of topic. Even with the info in your OP there's not enough for us to give you a meaningful example. It could be "worth" it either way depending on additional specifics. It's more meaningful for us to start with a better understanding of your credit profile versus jumping to this question.
In terms of store cards in general, they can be useful if you shop a lot at the given store and can make use of the benefits of the store card. However, if you need to build your credit profile it's possible that a credit card may be more versatile and possibly of more use to you. An additional general consideration is that you shouldn't be spending what you don't have.