We are now told that the Shower Pan Liner needs to be replaced, for which we received a quote of $10k!

Also consider the future replace cost and maintenance.

There are 3 major components to buying rental property.

If I decide not to replace the roof/AC should i then lower the price a little since it will definitely come up in the house inspection done by the buyer?

Have you explored the option of just replacing the rubber seal?

More importantly I looked at how technology could not only improve lifestyle but cashflow:(These are general numbers not associated to a specific product, please price your own product and charge +/- accordingly)30 Unit Apartment$150 deposit per 2 "smart keys" (returned if 2 undamaged keys are returned - kept if not returned)= $4,500 on deposit at capacity$75 replacement - This will bring in a few hundred a year minimum on this property(Make sure your replacement cost to the tenant is more than your key cost for the hassle of reprogramming and to be paid for your time and cashflow, consider it like a contractors markup for services)If I pay $200 a lock I am in for $6,000. however in year 1 I receive $5k+in deposits or replacement fees that could be realized.

So I will have to buy another MH to replace this one or set the land up for a few pads (2-4) and rent the land really dont want to own the MH if I don't have too.

Landlord remains responsible for major systems (heating, A/C, roof) and replacement of appliances if one is not worth repairing.

I guess the gold nugget is to find a 0.75% property in a neighborhood that has low taxes and that has most of the CapEx (roof, heater, AC) recently replace and hope your tenant stay for at least 2 years (that's why I'm so focused on good school districts). 

I replaced the knob handle and placed a stem extension.