.- A door to allow access from the main unit to the rental internally [ this is largely optional, I might consider just covering it up with board if thats a cheaper alternative.]- A kitchenette.

@Tammy SkeathYes, co-signers are a good alternative to accepting a tenant.  

Focusing on desired appreciation and time frame first might be helpful -how much ideally do you want to appreciate and when do you want to sell you'll need this to be able to calculate your Net Present Value to  make sure that you wouldn't be better off with alternative asset classes etc. - in beginning to narrow it down to an actionable plan - then - once you have an idea you could think about risk you're willing to tolerate and then how involved or not you would want to be in managing the asset/s.

Alternatively, do you have a better/easier solution?

I know there are other avenues to fund the initial purchase and renovation of a BRRRR investment such as hard money and private money, but would like to hear alternative ways to fund the purchase and rehab of a BRRRR and pros/cons. 

However if you respect them and develop a relationship, they'll likely serve you better than any alternative. 

Once you close you can adjust your financial position with an alternate lender.

@Tyler Lee with prices rising all over Massachusetts a good alternative to some of the higher price cities I have found is Fitchburg and Leominster with the price point your looking for. 

Alternatively, use an attorney or Title Co for the first one, and use that as your template for any in the future.As for the timing, I'm not sure it matters much if it's before/after tenants.  

I want to put down as little as possible and am interested in any alternative programs that help do so.