If you're in an hot market (i.e. easy to rent), you can get away with holding less liquidity or vice-versa.

The reason you need a professional (3rd party) estimate is to support your security deposit withholding.

I've heard of IL strict deposit return protocol so either way give proper notice of intent to withhold in a timely manner.I withhold the days of rent it took to re-rent when I receive no notice. 

However if this was not the case you should be able to withhold a normal cleaning fee.

They can have interior inspections, but if the tenant refuses to let the government inspector into their home, the city cannot withhold your rental license or force their way into the unit. 

I was advised by a real estate agent not to withhold the full amount of rent or pay for them myself and deduct it from the rent.

If it's part of the written contract, the title company can withhold the funds from sale proceeds.Now that you've already closed, your likely option is to sue in court.

I see becoming an Agent as a sacrifice of time, energy, and money but in return I get all of the opportunities that come with holding the license. 

I totally agree you don't need a LLC at this stage in the game.LLCs are useful in Hawaii in avoiding the HARPTA (5% withholding when you sell a property as an out-of-state resident), provided the LLC is registered in the state of Hawaii.

If it were me, I wouldn’t withhold anything for that.