Scraping the property and replacing it with another home is possible, and what is a cost effective recommendation for a replacement. 

Due to the increased costs associated with the property, we are instituting a X% rent increase, effective 1 March 2019."

is who you talk to.You should read my blog posts at https://www.biggerpockets.com/forums/70/topics/181968-alabama-tax-sale-redemption-rights and https://www.biggerpockets.com/blogs/6547/68021-alabama-tax-sale-investors-and-improvements-protect-your-rightsYes, if you lawfully took possession you were allowed to make the improvements. 

You will find a ton of useful information to help you with your foray into real estate investing.See here for the Guides:  BP GuidesSee here for the FREE video series:  The Financial Independence BlueprintSee here for the blog:  The BiggerPockets BlogSearch MeetUp.com for local meetups.And check out the New Orleans Real Estate Investors Association (NOREIA)Best of luck to you!

Although he's big on some pre-internet tactics such as door knocking to ask if people had friends or family interested in buying a house, and wanted me to go to realtor's and mortgage lender offices to make connections with them rather than call, some might argue these are still effective tactics.

Here is a link to help you out https://www.rentcafe.com/blog/renting/states-best-worst-laws-renters/Happy New Year:)

Are there any marketing tactics that stand out to you as being most effective ?

Has it been cost effective or positively impacted your brand?

https://www.biggerpockets.com/blogs/11212/79827-wait-before-you-spend-a-penny-investing-in-detroit

They state that the treatment last used (one building 1992 and other 1996) is losing effectiveness.