I see you are in Orlando, so I imagine your options are Spectrum and maybe FiosI usually go with 300 or 400 mbps depending on options and price (changes all the time). 

. - with this, we can potentially increase rents by up to 145% depending on a comparison with baseline 1977 level rent amount.I have 2 questions:1) If there exists these 2 other, legal ways to increase rent in a rent controlled area, why does it seems like the only option most investors consider is cash for keys?

Your rehab costs, this is the hardest to calculate, will depend greatly on location I did a mostly cosmetic rehab in dc was 160k did a similar project just a 1.5 hour away it was 60k, materials assuming your not doing something super high end seem to be 25-35k for a a sub 2k square foot house, again labor is tough to calculate, but ask around your local market what people are generally paying for things4.

There is a flat fee depending on amount needed.

Kind of like appraisals one surveyor is doing their math one way and it does not match anothers.. also depends on where their controls are .. do they have to go half a mile away to find a control point to then measure back in..   

Will depend on several factors like the type of property, type of tenants, your risk tolerance, other assets you own, your estate planning, laws where the property is located, etc.

Curious if anyone could provide rough cost to use when estimating for A/C replacement in Phoenix and Tucson Metros, ideally 3-ton, 4-ton, 5-ton replacement costs to account for varying home sizes.

It also depends on how many properties you plan on holding, renting,etc.

You should be taking out a HELOC or doing a cash-out refi(depending on your interest rate). 

A loud noise can mean many things, it depends on what the noise is.