Hello
Ah where to start in this world of crypto

Basically I have land that as been offered free electricity for the foreseeable future which of course is fantastic for mining and a group of investors willing to put down hefty sums to start the project off.
What i would like to know is firstly should i go for only gpu mining or only Asic mining ? asic can mine more but Gpu has good resale value when it comes time to upgrade or its no longer profitable, or perhaps 50 / 50
and what would be the best card or miner to go for based on fastest ROI ( again money no issue ) I can mine from my own PC at home and set it up fine no bother but running a large and ever growing farm is going to be a completely different kettle of fish. Could anyone please offer me any advice about any of this

bitmain have chips for all the algos, asic resistance is futile. decentralization is a pipe dream that is going to end because goliath always wins. unless we find a way to print chips in a 3D printer

That's a good resources you have but with no proofs and no transaction you have here in this forum no would believe you how you can access with it. Put some legitimacy of the site where you conduct that free electricity.

Sell back electricity to the person who gave it to you for free!

This is actually an awesome idea in theory. Not sure how and why power companies would allow it though, because even with solar net metering setups, the power companies are thorough and inspect the power feeds because obviously it could affect them negatively as well.

But most likely the OP doesn't really have free electricity and sooner or later it will bite him back in the butt.

One other option.   Get some big electric extension cords / net metering and sell that 20 kw back to the grid

20kw at 12 cents per kWh is about 21,000$ a year. You won’t get that though depending on local laws you might on net metering plans

25 x l3+ antminers in free electricity of 20 kw earns about $15k right now less cost of 25 antminers ($3k used on eBay) So net $12k year one

You are better off selling the electricity to neighbors if you can back feed it some how like solar net metered services include

If you go crazy and put out in some bigger miners that cost way more up front and longer roi maybe you can out pace that for profit of just selling the the electricity

For example 60 x z9mini is about 20 kw.  That’s about $50k up front shipped.  And daily profit dropping fast I’d expect an average around 3$ a day over 12 months best case. That puts at about $1k income per miner   I know today th looks great at 10$ to 15$ daily. It’s dropping fast and avg 12 Month income
daily could be under $1 due to difficulty in a few months.  It’s a gamble you roi at all even with free electricity based on past antminer releases the last 12 months - and you have to spend a lot to find out versus that used eBay l3 antminers  I suggested is guaranteed slow grind profit. Even if litecoin dificulty grows you will roi that hardware when bought used

That's good for your health. 
You can rest all night without worrying about coins price, electricity bill, etc. lol.

How can you get it? (free electricity - just curious about it) - Don't worry, your secret safe with me! 

How long have you done mining with this free electricity? How about your profit so far? (with current machines that you have)

With free electricity, whichever mining tools you are using, you are on the green zone!

Newest ASICs miner (whichever algorithm) will be the best choice for your condition related to maximizing your profit.

If I were you, I'd do solo mining all the time with my GPU rigs.