Build garage apt| Remodel | Buy another rental

[Luke H.]

What would be the best investment and why?

Should I keep looking for more rental properties to buy, fix, rent? (I think it is a seller's market in Houston).

Should I use the extra land I have on (in demand areas) of town and build garage apts (1 bedroom) to rent out for extra income or as airBnB?

Should I remodel the 2 bedroom/ 1 bath houses I have to make the 3 bedrooms/ 2bath and increase the rent?

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My initial plan was to build a garage apt (Ga) behind the house (Ha) that needs a full remodel.  Move into the garage apt (Ga) and remodel the house (Ha). Then rent out the house (Ha). Next, build another garage apt (Gb) behind another house (Hb), move into that garage apt (Gb) and remodel that house (Hb) and rent out (Ga). 

Now I'm wondering if instead, I should focus on finding more houses to buy and hold until I run out of capital and just keep fixing up the other houses when they need repairs.  This way the property tax bill stays as low as possible for the older houses and my net-worth grows with each rental purchase.

Feedback?

Thanks!