We see a tightening or restricting of coverage, higher deductibles, more tedious underwriting requirements, and increasing rates.As far as deductibles specifically, it really depends where you are in the country. 

This will all depend on how good of negotiator you are. 

Depends on the area.

It depends on a lot of factors; primarily the local jurisdiction rules that may limit lease changes (in Portland/Oregon rent, security deposit, screening fees, an no-cause evictions are heavily regulated).

It can get pretty expensive what would anyone suggest or should I write the lease so that the next tenant depending on time of year should I do not include a specific utility and adjust my rent because of it ? 

I understand that starting out, depending on how fast you want to build your portfolio, you could spend a lot of time at it.For those with established investment portfolios, how much time is required to maintain it?

It  depends on your risk tolerance and what other assets you’d like to protect.

Choose the Right Property:When choosing a house to flip, search for properties in desirable neighborhoods that need structural or cosmetic improvements.

Quote from @Paul Lucenti: It depends what you're looking for.

Whether you choose to run screening before you show the unit to them is a personal choice.