I obviously do not know your ultimate goal but I always recommend factoring in at least a small percentage of the rent towards those things for a rainy day.

Utilities are not simply a percentage of income. 

In LA, the expenses ratio "rules of thumb" point to much lower percentages because rents are so much higher (and, side note, the weather is considerable better).The 50% rule says that you should expect 50% of gross income to go toward expenses.

if so is it less of a percentage doing it with a FHA?

What percentage of expiring leases will renew their lease each month?

Do lenders reduce the LTV percentage in a depressed economy?

What’s average percentage rate for hard money what are you getting?

I'm not sure how much i can cover but let's say 30% of the total cost of construction.It terms of overall costs and interest percentage, would this be better than getting a home construction loan that roles into a mortgage with a one time close for the entire project?

There’s so much conflicting data on the web about what the actual percentage is.

You want to determine the percentage, points and amount you you are willing to lend.