If you do not have a budget for paid ads, then diversify and look for other alternatives to post your ads for free or at least get your money back with profits if you are going for paid ads. Here are some alternatives to the once famous Sulit.com.ph / Olx.ph.
I have screenshot the alexa rankings of these sites to see a comparison of how well they are doing. They are still far off compared to Olx but has potential for growth.
If you notice I have included Clixsense and Neobux in the comparison because these are the sites where I get most of my referrals in any of my work at home online jobs programs. Though these are paid ads, I get my money back with profits so I am not at a loss. I get my money back in the form of doing their daily jobs, referrals from other sites, and sales commissions from online products.