The H tags are heading tags that format your text into headings. H1 is the most prominent (largest), H2 the second, and so forth. You need to mind the content of each heading tag, it's probably a good idea. What he is essentially saying is that the search engines look to these tags for relevant meaning for SEO. Don't fill them with junk, essentially. I would advise you to take help from web design tool like Topagentsite
which is specifically designated for real estate investment.