Depending on what your lender approves you for, you can raise your home-buying "power" by lowering your debt-to-income ratio (paying off: student loans, car loans, CC debt, private/personal loans, HELOC, etc.) and can try again when you find yourself in better position.

I'm now under contract and WE have zeroed out all of our CC balances resulting in scores of 820 and 760 respectively - was told by my lender that as long as we're above 760, there isn't a big difference when you go higher than that.

No one bid on the units I was interested in (CC annual auction took place just a few days ago) - Would anyone know what are my options of purchase now?

If you refi a property to buy another property you have those CC then you will probably refi the property you just bought and have more closing costs.

If I'm purchasing a single family that's currently with a 1-year lease (tenant paying 745/mth) and the sales price is 20k ( but at closing, I'm buying for 25k after CC and other fees).

I have LOC's personally but those are local commercial banks with deep roots in the community and a very long term relationship with.. national lenders you never know you can make an app and the computer spits out an approval.if you go down the CC route just be careful.. and make sure you pay them off once you get into credit card debt its tough to get out. 

If so I know the Bronx has areas, but not sure you'd want to sacrifice location by living in a C/C+ area... 

To me I think the answer to that question is one of scale/range.I think it depends on how many houses you have and what the average monthly profits for your rentals are.Assuming you're netting 150/mo to 200/mo per house:1) When you have 1 to 5 houses , i think 20k is a good number for reserves provided you have some credit card and/or repair store card credit as well (i.e. 10 to 20k in available credit there as well).2) 6 to 10 houses I think 25 to 30k plus cc.3) 11 to 20 I think 30k to 40k plus cc.4) 20 to 30 50k to 605) 30 and above 75kAt some point, your profits almost become a reserve.

Another question, with my goal of buy and hold, I would be tying up a large portion of cash for the dp and cc.

Cc: your attorney at the bottom of the letter.