They might expect me to use that money I borrowed on credit cards to pay the bank off at closing.  

I also give them a choice of loan processing companies to escrow their taxes and insurance after the sale. 

Because of electricity generation and transmission losses, electric heat is often more expensive than heat produced in homes or businesses that use combustion appliances, such as natural gas, propane, and oil furnaces.If electricity is the only choice, heat pumps are preferable in most climates, as they easily cut electricity use by 50% when compared with electric resistance heating.

You can borrow up to 50% of the purchase price to rehab/upgrade the property.Upen Patel, Mortgage BankerFederal NMLS# 1374243

However, it seems like you are looking for your first fix/flip, wish to borrow 90% from a hml and the other 10% from another investor.

or should I pay apply it to the principal mortgage and have further equity I can borrow against.

When there are disagreements with the potential borrower we do provide a dispute process allowing the customer to have us take a second look at the evaluations. 

I would add in that you can buy on the date of their choice.

@Marvin Meng - that maxim about "If it's a real deal, you won't have trouble finding money" primarily applies to wholesalers who are trying to sell properties to investors by assigning the contract (it needs to be a real deal for the investor - if it is, someone will buy it) and to situations where you are partnering or syndicating (bringing on other investors as part owners) where you have an established track record and a good deal that people will be willing to buy into.Starting out to buy and hold or flip- you need your own capital OR you can borrow from 401k (cheapest) or credit cards (some are cheap or can be kept that way by rotating through various low interest deals) or you can borrow from family and friends and make it worth their while OR you can look for seller finance deals.  

The letters were "professional" and explained how I can help add value to their home sales process by buying as is, for cash, close on the date of their choice, etc.