I would like to congratulate you on taking the job, and more so for wishing to bring the property up to a higher level where possible.
There is to be some consideration as to what type of rental assistance funding you are under. In some cases this will make a difference in what monies are available to repair or improve the property. It will depend on who the finance agency is, and what are the standards that will be required for the level of maintenance. In most cases, long gone are the unkempt rental assistance properties of yesteryear.
You need to have a copy of the property budget. In many cases, this breaks out what is available for "O&M" or Operations and Maintenance. In the case you may be working for a private owner, who just happens to accept HUD, then you may not be privy to the budget at all, and may be excluded from that aspect. However, if your working for a property management company, I feel you, as manager, are entitled to a copy of the property budget, month by month. Usually, there is little extra money to be found in a standard budget, unless not much has ever been spent in the past. In these cases, the government usually makes a "Return to Owner" on the unspent money, who promptly pockets it as profits.
The cheapest and greatest upgrade on some properties are the simple planting of flowers, and neat and pretty entrances, porches, but not knowing your set up, this might not be a factor.
I suggest you tell us what "could" be done, and how the tenants would react to your asking for their help in beautifying the property. (Don't worry, I understand if the tenant aspect won't get you much help).
If your under HUD, those folks will mostly just make you meet the standards of occupancy, so not much help there. Again, if HUD, there is help from them in getting rid of non-payers, dirtbags, etc, so feel free to talk to them if you have problems.