Please these answers are based on latest version of Classibase version 1.4.6
Can I limit listings by cost, such as how many images can be uploaded, length of text included, maps included, etc? –
No, all that settings are valid for all paid and free listings. It is not possible to build custom packages with different features for different listing price.
Can I set listing expire dates by cost such as one month $1 or 3 months $2 – No, as explained above.
Any best hosting suggestions? – Bluehost, have tried it for other projects before.
Will you help me if I need it and will that help cost me? – No, unfortunately we do not do custom development for clients. You can try other classifieds scripts, some of them may have custom package building options, exactly as you asked above.