The seller and I have agreed upon pricing and I am in search of a buyer for rent or a flip.

Doesn't mean that you won't be able to find a buyer if your house hits the market in Jan/Feb, but you may have to hold a little while to get the price you want. 

Absentee owners.Asking price reduced $15k in June.Here is my question:In order to be a cash buyer, what is the best route to take if I, personally, don't have the cash reserves? 

So if I get this house I am looking at under contract and the owner lives there, how do I go about doing a showing with an end buyer?

I also have the option to partner (silent) in with someone who is willing to invest up to $100k for 50% of the deal which will basically just buy me the property, but i'd still have to come out of pocket for the reno.Not sure if either sound appealing and wondering if anyone has a recommendation which might be the better choice if any at all.Many thanks

That's why the buyer went to the other street & why the seller on your street had to put it on sale to get it sold.Never rent in owner occupied areas. 

It is mostly materials and I won't need to use a GC as the electric and plumbing are all basically new.

However, you can still run into issues if you finance the wrong buyer and they stop paying.

Most of the answers to the basic questions you're asking have already been answered here numerous times.There are plenty of free guides here on Bigger Pockets - starting with "The Ultimate Guide to Real Estate Investing" https://www.biggerpockets.com/files/329/download.

Example: Property goes under contract with distressed owner /=/ property gets marketed to cash buyers /=/ another wholesaler comes along interested in the property with a cash buyer in hand ready to buy /=/ contract gets assigned to secondary wholesaler /=/ wholesaler assigns to end buyer and closes within the contracted time frame of the original owner to wholesalers contract.