You'd have to speak directly with a lender on this one. From what I've seen, most lenders have made their guidelines more strict and raised the minimum credit score that they like to see from 620 to 660 or higher. There are lenders and programs for those with lower scores and/or a tax lien, but it's a case-by-case basis by the lender.
It sounds like you're doing the right things and it shows through in your credit scores increasing so you should be fine.
If you'd like the name(s) of a reputable and experienced lender in the area, just let me know. (One lender I use very frequently is based in Leesburg)