Here's why:  In order to complete a repair, the home warranty company must be contacted with the home warranty number and the owner's credit card information. 

@Kyle Mccaw you bring up a great point with post-cards having to at least have the message visible.

While you're getting familiar with your target areas, partnering with agents and brokers, and learning stuff... go knock on as many doors as possible and hand out your card.

Hello,What is more valuable when starting a credit card to build my credit score, an unsecured or a secured card?

Take all your monthly debt payments (credit card, car loan, mortgage, student debt etc) and divide that total by your gross monthly income. 

It kind of depends on your needs-- my bank counts the full amount of the HELOC as credit card debt :(  So if you use all of it and/or don't make consistent progress paying it down, your credit score could take a hit.

How fast your credit score reacts to the changes you make depends on what is influencing your credit score down but most often if it is not negative credit then it's your credit card balances are maxed out or close to being maxed out.  

also be very careful of advanced fee schemes that are rampant on the internet and here on BP you may get a PM  hey howzit  you looking for a loan then back and forth then your approved magically all U need is to send them 500 to 1500 bucks to do the docs and the money has to be in gift cards or some silly thing like that.. 

Art, metals, property, hell even collectible old baseball cards. 

Aside from that, most people starting out will use some/all of the following to fund rehabs:- friends/family- side hustle- credit cards- home equity line on current residence- personal loan at bank- ETC