There are defined standards and easy to use.

While "regular" here isn't defined in the statute or regulations, the Soliman SCOTUS case tells us that for a home office to be "used on a regular basis" the use must be "substantial". 

You will need a surveyor to define where the new lot lines are.

Success isn't normally defined by one event, but by a road well traveled.

You really need to define your investing goals and then pick a strategy that fits those goals.For me, I decided turnkey properties fit my goals to get started with investing (see post below).https://www.biggerpockets.com/forums/850/topics/895660-my-first-investment-property-an-out-of-state-dealBest Wishes!

First thing with real estate investing is to clearly define your goals.

You analyze markets by finding the common properties, based on size only, and find the groups of them where they reflect the same $$$$, for three monetary events:1 - Entrance - Cost to buy2 - Exit - a)  Sold Comps; b) Rental comps3 - Spreads between 1 and 2a (cash flow), and between 1 and 2b (profit) Here's what I mean:1 - Pick any area2 - Record all the properties 4Sale on the map of that area (yes, plot them on the map)      a)  Size (the ranges are defined by/where the mean of every range no more than 10% away from the highest and lowest sq ftg defining that range).     

Can someone please define portfolio lending for me.

It is defined as RC - depreciation. 

If you're clear on your goals, you can define your path.