If you have worked with the contractor before and it is a easy material list, I do not see an issue with purchasing material and getting some credit card points.

If you start an LLC go get a business account with a bank and apply for business credit cards.

These added expense can be accounted for but that doesn't change the wild card of hoping your tenants don't ruin your leach field.

Obviously speak with lenders, your CPA and lawyer, but its very common for folks to start out owning residences themselves vs corporate entities, and just having some sort of liability insurance.If you do get an entity and what business credit, if I remember correctly you just need to register the entity with HMRC etc, and start out getting a credit card with whichever bank you choose to open a current account with.

My current card was issued in 2012.. 

However, my primary focus has been paying off debts that I've unfortunately accumulated over the past couple of years (roughly $2k in credit card debt, and a car payment with about 13k/4 years left on it).

Also look at how often they had late payments on credit cards.

Intention is to have a parent holding LLC with subsidiary LLCs to hold assets, form joint ventures and possibly one as a holder of interests in foreign entities (we may do some investing in South America too).My wife/partner is a foreign national in the US and does not have any US based documentation (no Tax ID, no Green Card, no SSN, etc) at this stage but we do intend for her to get residency documents in the next couple years.The plan now is to incorporate the LLC(s) beginning in January with myself holding 50% and my foreign national wife holding 50%.  

The 5K is on a credit card with 0% interest for 12 months. 

It's going to be a combination of classic Victorian style and farm house.