Things like title insurance, surveys, property taxes, lease backs, home warranties, and any other expense.Another issue is timing....my guess is in Denver homes move pretty fast....that means they go on the market Wed/Thur and deadline for offers is Sunday night/Monday morning.   

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If it's not strucutral, I would say don't worry about it.Professional consulatants for plans/surveys could take a couple of months to get approved by local jurisdiction. 1 month to make plans/survey and 1 month to get approved by city. - not including revisions

However, I did my own research with Exp Realty which they do provide the licensees with all the trainings online, multiple listing service membership and flexible hours that I learn and practice after business hours.

I responded by saying, well if we buy it, I'd get a survey done, to which he responded firmly, WE DO THAT ON A HANDSHAKE.

Some are monthly memberships vs. per unit. 

For instance, when laying out the ADU floorplan on the site, it's advisable to leave an additional 12-18" beyond the allowed 4' side and rear setbacks to avoid a costly building location survey. 

I bought Brandon Turner's Intention Journal which comes with a mastermind membership.

I bought a hootsuite membership and set it to share 3-5 houses per day with calls to action. 

My Budget is about $300 a month for Programs/Tools (Data Base, Driving for Dollars App, CRM, and Potentially a Basic Website that is actually included in my REIA membership.)