It isn't bad or good, it all depends on a persons goals and level of involvement, or lack of involvement, that they want. 

Depending on how long they've been on the market, desire to sell, etc, the seller may consider your offer.  

You success is going to depend upon your ability to be consistent.

depending on where you're looking.... you might find it extremely hard to get a deal on commercial side.

If you are doing it in excel - a receipt for $100 that consisted of $25 paint, $25 tools, $50 roof supplies.can be entered into excel like$25 paint$25 tools$50 roof suppliesAt the end of the year you can sum up all the costs by description and provide that to your accountant.A couple things to point outWhether you expense an item or capitalize it will depend on several factors such as if you are increasing the useful life of the item, making it ready for a different use or making it more efficient.

That will determine what your offer will be.  70% is not a rule and it varies from 30 to 80 depending on heat.

Someone with expertise should be able to quote a flat rate for the entire project and for each stage of the project.I would expect a lawyer to charge more if getting paid depends on future events, because that means more risk for the lawyer.

Depending on how much you are trying to borrow, the $10K might be used as DP.

Depending on the cost it may need to be capitalized and depreciated.

Depends a lot on how you plan on doing it.